AUI-1300 Make aui-datatable work on touch devices

Making a few changes to datatable so it will work well on touch devices:
(1) Property lists used to have double click as the default edit event. I changed this so that it will use click instead when on a touch device.
(2) The datatable editors are now constrained to the viewport, to make sure they'll always show up in the small screens.

Also added datatable-scroll to the demo as an example of how to add scroll to the datatable.
AUI-1332 Source formatting

Signed-off-by: Henrique Vicente <henriquevicente@gmail.com>
AUI-1332 Fix dependency injection and add form build field types inside the A.FormBuilderField.types namespace

Signed-off-by: Henrique Vicente <henriquevicente@gmail.com>
AUI-1450 "Load More Results" always loads again and again last elements despite of there aren't more nodes
AUI-1450 TreeView should not show more nodes than what's defined in paginator.total
AUI-1450 Adding tests
AUI-1450 Fixing tests
AUI-1342 - A User is unable to deselect their previous selection in a Datatable with Selection and Highlight
AUI-1342 - Source formatting
AUI-1342 Source formatting
AUI-1454 Make lint, test, and test-browser end with an error exit code in case of failure

By adding the jshint fail report and passing the test / test-browser callback arguments back to gulp.

Related: https://github.com/gulpjs/gulp/commit/2504d1612565173b160050e8a1690aa0f28f2d84
Signed-off-by: Henrique Vicente <henriquevicente@gmail.com>

AUI-1454 Make lint, test, and test-browser end with an error exit code in case of failure

By adding the jshint fail report and passing the test / test-browser callback arguments back to gulp.

Related: https://github.com/gulpjs/gulp/commit/2504d1612565173b160050e8a1690aa0f28f2d84
Signed-off-by: Henrique Vicente <henriquevicente@gmail.com>
AUI-1356 Use 'for' as the preferred way to find field label
AUI-1356 Source formatting
AUI-1300 Changing css so the scrollbar will only show up when necessary
AUI-1455 Change listener method names on ImageViewer modules

Listeners should each have a separate method, even if that method will just call a single function, as that later helps people to extend our modules. The image viewer modules had lots of listeners that are not following this pattern, so this is fixing those.
AUI-1528 Drop Zone on Form-Builder Styling is off
AUI-1532 The gulp watch task doesn't work for css files

Gulp watch doesn't rebuild the module when css files change, like grunt task used to do. This is just adding one more path for the watch to work with css as well.
AUI-1532 Remove duplicated glob
AUI-1529 Change width ratio of form builder columns

The form builder's 2 columns were taking 50% of the page each. That doesn't look good for the first column on big screens though, so adding a few more bootstrap classes to make the percentage smaller for the first column on bigger screens.
AUI-991 Add events to audio and video modules