feat(bsDatepicker): enable attribute-driven language change

If the language changes, the directive should immediately change the language of the datepicker.
Currently, as there's no such method in the datepicker plugin
(see https://github.com/eternicode/bootstrap-datepicker/issues/362), a change is forced by
reinitializing the datepicker itself.
Also, a check has been added to the `regexpMap` function, in order to handle cases when the language
passed to the directive is not present in the datepicker's languages.
The `datepickerSpec` module has been updated accordingly with a test checking the new behaviour.
fix(grunt): `grunt build` had trouble building because of an unused option in `uglify` task
Merge pull request #265 from frapontillo/feature/datepicker-change-language

feat(bsDatepicker): enable attribute-driven language change
Use more chaining to simplify code
Merge pull request #266 from sja/patch-1

chore(popover): use more chaining to simplify code
Merge pull request #267 from RobJacobs/master

fix(select): handle changes to the option items
feat(release): cut the v0.7.7
feat(bsSelect): enable validation on the selectpicker
fix(select): part 2, bind on required attribute changes

The `bsSelect` element should handle its own validation CSS classes by deriving
them from the original select `element`.
The validation is checked when one of the following changes: `$modelValue`, `$viewValue`, `attrs.required`.
Merge pull request #270 from frapontillo/feature/select-validation

fix(select): validate the select element if required on the original one
Avoid call to $apply to improve performance

The function does not change the model so we can prevent $timeout to do the $apply. The performance improvement is very noticeable with a lot of instances of the directive (+30)
Merge pull request #1 from jacarma/patch-1

Avoid call to $apply to improve performance
Merge pull request #275 from jacarma/patch-1

chore(button): avoid call to $apply to improve performance
select/options: $parse instead of simple key lookup in the scope
select: disable listening for DOM updates by selectpicker
Merge pull request #290 from uxmaster/master

fix(select): issue #245 fix, pull request #267 bugfix
feat(modal): add support for bs3 (fixes #272)
feat(tooltip): add support for bs3 (fixes #277 #278)
feat(button): add support for bs3
Merge branch 'master' of github.com:mgcrea/angular-strap