erp5_web_renderjs_ui: html5_select: event option for notifyChange added. needs for determine event.type on parent gadget

i need it because use span for displaying icons in json form

This is needed when running livetests in a runUnitTest instance, in the
following scenario:
 - `runUnitTest --save test_bt:testXXX`
 - `runUnitTest --save --load`
 - run the live test from the browser

because livetest way of processing activities is to unsubscribe at the
beginning of the test and subscribe at the end to have control of
activities when running .tic, if ProcessingNodeTestCase also process the
activities automatically, they interfere and test often fail with errors like:

```
File "ERP5Type/tests/ProcessingNodeTestCase.py", line 249, in tic
  raise RuntimeError(error_message)
RuntimeError: tic is looping forever. These messages are pending: [('/erp5/portal_components/test.erp5.testSupportRequest', 'immediateReindexObject', 1, 0), ('/erp5/support_request_module/2617', 'immediateReindexObject', -1, 0)]
```

/reviewed-on nexedi/erp5!779

This step just checks that multi relation field listbox shows a list of
related document and that clicking on any item of the list leads to the
related document.
The order of related documents in the list has always been unspecified,
but the first one was always 1 until recently.
Because this test does not really care which one of the two related
document was clicked, just assert that it's a document from foo_module.

/reviewed-on nexedi/erp5!774

89115b88 is great, but with "testFunctionalAnonymousSelection" the
result HTML is more than 40Mo.

/reviewed-on nexedi/erp5!772

This will insure that the URL created for diff by `Base_redirect` will have the paramters
`your_first_path` and `your_second_path` in it, thus making it unique and hence
sharable. Before, we only used to have the name of selection in the URL which
returned different result for different users.

also use '>' instead of image

Assorted fixes and new features for support request app:

Features
 * post are now HTML and use the preferred editor ( CKEditor by default )
 * posts are ingested in Web Message and the app uses same data model as erp5_crm ( so it is able to display support request created with "standard" ERP5 interfaces)
 * date of post uses momentjs relative time (New message by Bob 1 hour ago...)

Bug fixes:
 * post API no longer use proxy roles / immediate reindex
 * RSS was re-implemented to list events. The previous approach of listing support requests had an issue that the date of new posts was still the date of the original support request.
 * attached files to the "submit new support request" dialog where not uploaded
 * using a handlebars template we prevent html injection / XSS 
 * increased test coverage

/reviewed-on nexedi/erp5!769