docs(ngController): improve wording
docs(guide): add ngTagsInput to UI Widgets
docs(guide): add UI-Map to Complementary Libraries
docs(guide/index): add codeschool link
feat(attrs): trigger observers for specific ng-attributes

When an observer is set to listen on the pattern, minlength or maxlength attributes
via $attrs then the observer will also listen on the ngPattern, ngMinlength and the
ngMaxlength attributes as well.

Closes #7758
Merge pull request #8 from angular/master

update