erp5_web_renderjs_ui_test: reproduce validation error issue and add asserts to make sure field has expected class

* Trigger focus and blur to test renderjs functions properly
* Add asserts to make sure we don't lose value after raise Invalid Date
* Cover issue that invalid class does not disappear after click to create new object Foo in relation input
* Make sure fifth_failure input has invalid class
* Cover validation error to multicheckbox, checkbox and radio fields

* change the label field to not display the error text by default
* change all html5 fields (input, select, textarea) to add a custom *invalid* class when the field is invalid
* change all html5 fields to listen to the `focus` and `blur` event (with the renderjs onEvent method)
  Then, acquire (with `declareAcquiredMethod`) and call `notifyFocus` / `notifyBlur` methods respectively.
* change the label field to handle `notifyFocus` / `notifyBlur` (with `allowPublicAcquisition`).
  Change the validation error text display state depending on the field status
* Trigger onStateChange to set invalid class. If error comes from input field, we need to change state locally to set invalid class
* Regenerate gadget_erp5_nojqm.css from  erp5less.css using http://lesscss.org/less-preview/
* Textarea gadget should not prevent default when invalid event is triggered
* Support notifyFocus and notifyBlur in panel

Use reveal 3.9.2
Remove font not present from reveal theme.

See nexedi/erp5@ee81e26e (comment 121758)

See nexedi/erp5@ee81e26e (comment 121757)

that would return the whole catalog

Only basic fields are supported (no gadgetfield for now).

See merge request nexedi/erp5!1275

- this action relies on paged.js library for pagination

Don't log and fix a few resource warnings

See merge request nexedi/erp5!1307

Add missing field, used in testFloatFieldStep

It follows commit ce233f79

Some fields may use div element without expecting 100% width.
Example: formbox and diff gadget.

this prevents ResourceWarnings on python3

this prevent ResourceWarnings on python3

this is way to verbose and not really useful

Why invent a different way, making it harder to consistently patch
validated_hook ?

For example, allows upgrading a Business Template when an ERP5 Form is
replaced by a PythonScript in a skin folder.

When running on testnode, runUniTest is responsible for picking a free $DISPLAY.
This is implemented by starting Xvfb on a $DISPLAY, waiting a bit and if it is
still running we assume the $DISPLAY was free. But it seems sometimes we don't
wait enough, when testnodes are overloaded.

This implementation is wrong, we could run a command check that X is running,
but as explained in the code command below, xdpyinfo or other tools are
currently not available in test environment. Since we are considering switching
this to seleniumserver (which would take care of running a X Server for us) so
this is OK for now.

there was also another script for internal