Update .travis.yml

update sauce labs credentials (use the same one than delite)
Update .travis.yml

Revert last commit (restore original credentials)
JSDoc: remove @summary/description
Added Pageable mixin for the deliteful/list/List widget. This mixin
allows pagination of long lists.
JSDoc: remove a left-over @summary
SidePane to extend DisplayContainer
remove dojo/_base/win dependency
Improve LinearLayout usability:
 - Children automatically set to position relative to allow sub-children absolute positioning (percentages)
 - Sub-children with height 100% automatically set to position absolute