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.

lib/grunt/utils.js

@@ -146,10 +146,8 @@ module.exports = {
         'java ' +
             this.java32flags() + ' ' +
             '-Xmx2g ' +
-            '-cp components/closure-compiler/compiler.jar' + classPathSep +
-            'components/ng-closure-runner/ngcompiler.jar ' +
-            // '-classpath ./components/closure-compiler/compiler.jar' + classPathSep +
-            // './components/ng-closure-runner/ngcompiler.jar ' +
+            '-cp bower_components/closure-compiler/compiler.jar' + classPathSep +
+            'bower_components/ng-closure-runner/ngcompiler.jar ' +
             'org.angularjs.closurerunner.NgClosureRunner ' +
             '--compilation_level SIMPLE_OPTIMIZATIONS ' +
             '--language_in ECMASCRIPT5_STRICT ' +