tap_ipv6 option let you chose if you want IPv6 on the taps or not. Some
customers may decide to have only IPv4 inside their VMs.

We put only 1 address on the tap itself (e.g.
2001:67c:1254:e:89:69b0:ffff:ffff/128 instead of
2001:67c:1254:e:89:69b0:ffff:ffff/96) otherwise, when we assign the
address 2001:67c:1254:e:89:69b0::/96 inside the VM, the address has
"dadfailed" status (dad = "Duplicate Address Detection"). The problem
appears only with address "0" (ending in ::) but not with others
addresses. We had 2 solutions:
 * put only one address on the tap (the solution we choose)
 * forbid address "0" inside the VM

The chosen solution has the advantage that the host machine won't
answer the ping on behalf of the VM since the tap has only 1 address
(its own).

/cc @alain.takoudjou

/reviewed-on nexedi/slapos.core!86

This indicates on the transaction and on indexation that a payment was created for the invoice. This allow us to avoid duplicated creation due race conditions on activities.

slapos_payzen: Skip invoice if payment was created on the same transaction or if the payment wasn't indexed yet

  Otherwise it will lead to random failures caused by some race conditions

Update tests to follow up changes on the UI and replace repeated parts by macros.

There ins't a major change of behavious here

Speed up the rendering and only do xhr to update if the user stays long enough on the page.

This change will significally drop the number of xhr on the site.

It is not ideal, but it works quite fine (since 994d836996f8e762924b2898ef3a6385ad7d5759). Callable scripts should be used to avoid extra queries or calculations.

Reimplement the wrapper to follow up this change:

nexedi/erp5@f9c408f7

Implement a backend automated logic for Ticket management on hateoas UI. This interaction workflow replaces script calls, and custom inits for the portal type.

This inteaction workflow could be explited per impacted business template or moved into slapos_hal_json_style to be more consistent.

The call to web_message stop was replaced by an interaction workflow entry along with the dummy sets with values hardcoded on the UI.

In general, UI should be cleaned up to contain its minimal necessary for API and all the deeper logic should be implemented exclusively on the backend.

Update the fork of slapos with ERP5 Code.

Make it return to Home

This bt5 is not present on production, however, it is helpfull to have this script on a development machine.

 Follow up changes from ERP5 after the rebase

  This shouldn't be tested on this project scope.

  This test lacks the use case of same user transaction

 The Base.reindexObject is not called directly anymore, so patch a deeper level

assertNotEquals is deprecated since 3.2 (see https://docs.python.org/3.7/library/unittest.html#deprecated-aliases)
This is a followup of 175b5788

/reviewed-on nexedi/slapos.core!81

`test_one_failing_daemon_in_service_will_bang_with_watchdog` often fail with:

```
======================================================================
FAIL: test_one_failing_daemon_in_service_will_bang_with_watchdog (slapos.tests.slapgrid.TestSlapgridCPWithMasterWatchdog)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/srv/slapgrid/slappart9/srv/testnode/bpy/inst/test0-0/parts/slapos.core/slapos/tests/slapgrid.py", line 907, in test_one_failing_daemon_in_service_will_bang_with_watchdog
    'etc', 'software_release', 'worked', '.slapos-retention-lock-delay'])
  File "/srv/slapgrid/slappart9/srv/testnode/bpy/soft/5082e1741ad09c0910ec59bf9feae300/eggs/six-1.11.0-py2.7.egg/six.py", line 673, in assertCountEqual
    return getattr(self, _assertCountEqual)(*args, **kwargs)
AssertionError: Element counts were not equal:
First has 1, Second has 0:  'crashed'
First has 1, Second has 0:  'launched'
```

This test uses a service that will create files `launched` and `crashed` files
when running, and just after telling supervisor to start the service test
inspects the directory content.
If service had time to start, then files are created, otherwise they are not.

Change the service to wait for a delay before creating the files to reduce the
change of race condition here.

/reviewed-on nexedi/slapos.core!82

Slapos proxy was not really deleting the software, just removing it from its database but not telling the node that requester requested deletion.

As a result, node was not destroying the software and leaving the software folder around.

These changes are about telling the node that requester wanted destruction of software, so that node really delete the folder.

/reviewed-on !76

Tests are sometimes failing with:

```
======================================================================
FAIL: testForwardToMasterInList (slapos.tests.slapproxy.TestMultiMasterSupport)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/srv/slapgrid/slappart9/srv/testnode/byq/inst/test0-0/parts/slapos.core/slapos/tests/slapproxy/__init__.py", line 1003, in setUp
    self.startExternalProxy()
  File "/srv/slapgrid/slappart9/srv/testnode/byq/inst/test0-0/parts/slapos.core/slapos/tests/slapproxy/__init__.py", line 1050, in startExternalProxy
    self.fail('Could not start external proxy.')
AssertionError: Could not start external proxy.

```

especially on `COMP-2203-3Nodes-ERP5PROJECT2`. I logged on that machine and check the tests, it was really a problem that this slapproxy needs more than the `(20 * .1) = 2` seconds this tests waits before concluding that slap proxy could not start.

Change the waiting loop to wait more each time. With this approach the max waiting time is 20 seconds.

/reviewed-on nexedi/slapos.core!83

/reviewed-on nexedi/slapos.core!85

this XXX comment no longer apply

put back `related_predecessor_but_with_different_title_than_catalog_title` which was removed by commit 85c7fb26

/reviewed-on nexedi/slapos.core!80

SlapOS test is too verbose, see http://community.slapos.org/test_result_module/20181211-426F13FE/6 as an example. The main goal of this work is to make this easier to read.

Other improvements:
 * introduce `subprocess32` on python2 to use new subprocess features on python2
 * honor `SLAPOS_TEST_DEBUG` environment variable to output logs and also enable debugging utilities ( unittest's `Ctrl+C` handler )


/reviewed-on nexedi/slapos.core!73