When the user add, modify or remove a Calendar Exception, related Group Calendar Assignments should be updated.

This is a continuation of !261  implementing also the suggestions from nexedi/erp5@1fa90034 (comment 17234)


@rafael @tb @seb @romain @georgios.dagkakis 

/reviewed-on nexedi/erp5!631

Fix for [#20171205-E91759](https://nexedi.erp5.net/bug_module/20171205-E91759)

Basically extend the change from
24c836a7 to the case where there's an
exception, but the exception does not match and add tests to reproduce
the case.

/cc @seb @gabriel @georgios.dagkakis @Nicolas

/reviewed-on nexedi/erp5!630

Currently, it is in expected failure state as it doesn't behave similar
as XHTML UI.

/reviewed-on nexedi/erp5!648

In the promise file, the persistent memcached url were swapped

@georgios.dagkakis @Nicolas - moving test related things out of the erp5_corporate_identity template
test results: https://nexedi.erp5.net/test_result_module/20180419-563DDA29

/reviewed-on !645

[renderjs_ui] Move Form submission logic into one place - Page Form and add constants to Form Definition in [hal_json_style]

- allow slapos master communicator to supply software destruction
- runner reinstalls software on every commit (temporarily)
- refactor in software profile construction
- some try controls added

/reviewed-on !644

auto-generate expense sheet by using title and number

- before create a new instance checks if the current testsuite has an old one
- re-uses file-dictionary functions of frontend software checks
- minor fixes

/reviewed-on nexedi/erp5!615

Display relation field select list if focus is activated
Fixup click handling

(fix: e46ade7a)

(fix erp5.git/eb5f1fb1)

As it is a common pattern to set validators on hidden fields
to display custom errors to users.

By using `os.path.normpath` we also support paths with a trailing slash.

Also, change the JSON format and update tests according to these changes