[tooltip] Add text wrapping in a tooltip

[pkozlowski-opensource]

Currently text can't be wrapped in a tooltip. The original bootstrap directive allows HTML tags in the tooltips text but for us to support this we would have to either:

• http://docs.angularjs.org/api/ng.directive:ngBindHtmlUnsafe
• http://docs.angularjs.org/api/ngSanitize.directive:ngBindHtml (this would force us to require ngSanitize)
• other ideas?

The more I think about it the more I'm getting warmed up to the idea of using ngSanitize...
@angular-ui/bootstrap thoughts?

[joshdmiller]

I agree, @pkozlowski-opensource. Though I really don't like having to require ngSanitize, I like the alternative a lot less.

angular-sanitize.js is only 3.8K. For reference, angular.js is around 78K and ui/bootstrap is currently around 20K, so that's only an increase of about 4%.

Unless there are objections (or a better idea), I'll submit a PR this weekend.

[pkozlowski-opensource]

@joshdmiller yes, as much as I hate adding new dependencies I'm pretty much resigned to the idea of including dependency on ngSanitize :-( Unless someone can see another magical solution... Bumped into this once again today while working on the typeahead.

PR would be awesome.

[pkozlowski-opensource]

Duplicate of #246