Improve feedback in forms

[Ana06]

Add html5_validators gem, which provides automatic client-side validation using HTML5 based on the models validations. This makes much easier to keep views and backend code consistent and
provide early feedback to users. This is also changing many forms in the whole application. It should be though a save change as it is consistent with our model validations and the errors would have just been shown later.

I have removed from our views code SOME of the html validations that are now provided by HTML5Validators, by using our models validations. There may still be some repetition and differences but I had to stop somewhere. In the future when realizing of the discrepancies, it should be as easy as remove the view code. Some more PR for more validation improvements are coming.

I have also change some emails fields to use email_field Rails helper, which generates a text_field of type email, providing feedback to users when introducing a wrong email without sending the form.

It helps addressing #7011.

[Ana06]

[Last card] Address feedback/issues

[coolo]

And once again, the spider test uncovers crucial tests missing:

[979faece-c1e5-4d78-ac39-0b73b12863c4] [299:68.43] ActionView::Template::Error (undefined method `auto_html5_validation' for Patchinfo:Class):
[979faece-c1e5-4d78-ac39-0b73b12863c4] [299:68.43]     11:             %strong
[979faece-c1e5-4d78-ac39-0b73b12863c4]     12:               = f.label(:packager, 'Packager:')
[979faece-c1e5-4d78-ac39-0b73b12863c4]     13:             %br/
[979faece-c1e5-4d78-ac39-0b73b12863c4]     14:             = f.text_field :packager, required: true
[979faece-c1e5-4d78-ac39-0b73b12863c4]     15:             :javascript
[979faece-c1e5-4d78-ac39-0b73b12863c4]     16:               $("#packager").autocomplete({source: '#{url_for controller: 'user', action: 'autocomplete'}', search: function(event, ui) {
[979faece-c1e5-4d78-ac39-0b73b12863c4]     17:                 $(this).addClass('loading-spinner');
[979faece-c1e5-4d78-ac39-0b73b12863c4] [299:68.43]   
[979faece-c1e5-4d78-ac39-0b73b12863c4] [299:68.43] app/views/webui/patchinfo/_form.html.haml:14:in `block in _app_views_webui_patchinfo__form_html_haml__1383717022713791384_47354342968160'
[979faece-c1e5-4d78-ac39-0b73b12863c4] app/views/webui/patchinfo/_form.html.haml:2:in `_app_views_webui_patchinfo__form_html_haml__1383717022713791384_47354342968160'
[979faece-c1e5-4d78-ac39-0b73b12863c4] app/views/webui/patchinfo/edit.html.haml:3:in `_app_views_webui_patchinfo_edit_html_haml__1907723402339578054_47354343006520'
[979faece-c1e5-4d78-ac39-0b73b12863c4] config/initializers/wrap_parameters.rb:38:in `call'
[979faece-c1e5-4d78-ac39-0b73b12863c4] test/functional/webui/spider_test.rb:99:in `crawl'
[979faece-c1e5-4d78-ac39-0b73b12863c4] test/functional/webui/spider_test.rb:161:in `test_spider_as_admin'
[979faece-c1e5-4d78-ac39-0b73b12863c4] test/test_helper.rb:118:in `block in __run'
[979faece-c1e5-4d78-ac39-0b73b12863c4] test/test_helper.rb:118:in `map'
[979faece-c1e5-4d78-ac39-0b73b12863c4] test/test_helper.rb:118:in `__run'
[299:68.67]   �[1m�[35m (0.3ms)�[0m  �[1m�[31mROLLBACK�[0m

[Ana06]

I don't think I'll have time to finish this in the close feature. I still think it is a nice gem that could help us keeping OBS consistent. It may require a bit of work on the gem though. If someone would like to finish, feel free 😉