Added support for ng-animate (from branch issue-22, closes #22)

Squashed commit of the following:

commit c24a6a6
Author: Karsten Sperling <mail@ksperling.net>
Date:   Mon Apr 15 17:40:12 2013 +1200

    Detect if $animator is present and fall back to plain old DOM manipulation otherwise.
    Also call $compile only on the element we're adding, not the container node

commit e080bc4
Author: Karsten Sperling <mail@ksperling.net>
Date:   Sat Apr 6 00:16:45 2013 +1300

    Workaround for text node problem (needs to be fixed upstream)

commit dacf4a7
Author: Karsten Sperling <mail@ksperling.net>
Date:   Fri Apr 5 23:56:09 2013 +1300

    Initial stab at #22, with some problems left to resolve:

    * If the template isn't contained in an element, text nodes get dropped (due to .children())
    * If we use .contents() instead of .children() the animator ends up calling $window.getComputedStyle on text nodes which throws.