fix(bower): update bower usage and resources

Changes:
- Fix our old code to use bower_components/ as the install dir
- Fix the Bootstrap asset to use github.com/twbs/bootstrap (it moved)
- Fail the build on Bower failure. Bower should not fail silently.
fix(ngdocs): make jsFiddle and Plunkr links work with external AngularJS modules
chore(ngdocs): fixed jsFiddle/Plunkr examples to include ngAnimate and use a default App the module is not set
fix(ngClass): ensure ngClass doesn't fire addClass or removeClass with an empty string

If ngClass fires off an add- or removeClass whilst the opposite animation is going on then
the animation will be skipped. The default behavior of ngClass was executing remoteClass
with an empty string while addClass had just fired. This commit fixes that bug.
chore(ngdocs): all animation-supported directives working with docs examples and jsFiddle/Plunkr pages
chore(bower): update to bower 1.0.3
docs(error): improve the cacheFactory/iid.ngdoc
chore(bower): write grunt task for running bower
fix(ngShowHide): change the .ng-hide CSS class to use an !important flag