feat(modal): add backdropClass option, similar to windowClass option

Really, identical to windowClass, but for backdrop.

Fixes #1179
Closes #1862
test(collapse): DOM elements cleanup
test(tooltip): DOM elements cleanup
test(datepicker): DOM elements cleanup
fix(modal): add a work-around for transclusion scope

Fixes #2110
Closes #2134
Closes #2143
chore(all): clean up trailing whitespace

jshint is failing.

Closes #2147
fix(alert): correct binding of alert type class

Regression from #1745 as there's a double interpolation expected but
ngClass doesn't support that.

The attribute value of ngClass is only interpolated once and the
interpolated expression is watched.

Fixes #2145
Closes #2146
fix(typeahead): allow multiple line expression

introduce [\s\S]+ to include both whitespace and non whitespace
characters

Fixes #1687
Closes #1850
fix(dateparser): do not parse if no format specified

Fixes #2159
Fixes #2137
Closes #2162
fix(tabs): remove leading newline from a template

This messes up jquery's parsing of the template

Closes #2200
Fixes #2106
chore(build): switch to node 0.10.x on TravisCI
docs(README): remove reference to bitdeli analytics

see: http://blog.bitdeli.com/post/77717727361/on-githubs-image-proxy
docs(CHANGELOG): fix code snippets

A few snippets were not wrapped in code blocks.

Closes #2245
docs(typeahead): use array.map to shorten async example
feat(modal): support alternative controllerAs syntax

Fixes #2242
fix(modal): allow in-lined controller-as controllers
docs(README): fix code samples formatting
Merge commit '6e83dc647ab7963cebb5efd0c6d328c7bf891a40'