fix(tooltip): performance and scope fixes

Isolate scope contents should be the same after hiding and showing the
tooltip. The isolate scope's parent should also always be set to the
directive's scope correctly.

fix(tooltip): link on demand

- Calling $digest is enough as we only need to digest the watchers in
  this scope and its children. No need to call $apply.

- Set invokeApply to false on $timeout for popUpDelay

- No need to test for cached reference when tooltip isn't visible as
  the tooltip has no scope.

Closes #1450
Closes #1191
Closes #1455
refactor(datepickerSpec): speed up tests

Tests were compiling the element multiple times unnecessarily as it's
done in the root describe's beforeEach.

Introduce describe blocks with no name to encapsulate tests that need
the element to be compiled and separate them from tests that have their
own compilation.

Closes #1499
chore(build): add banner into build files

Closes #1493
fix(modal): leaking watchers due to scope re-use

Previously, the backdropScope was being re-used and each time it was
linked, it would attach more watchers to the scope.

Closes #1491
Closes #1498
demo(all): use modal for download process

Closes #1494
demo(all): add HTML5 doctype

This prevents browsers from following legacy specifications such as what
was discovered on #1507.

Closes #1510
demo(tooltip): correct usage of anchor element

Tooltips were nested in anchor elements to get the hyperlink styling
from Bootstrap. This seems like an odd use of anchor elements and we
shouldn't encourage this. Instead, use anchors like actual links that
point to nowhere (#).

Closes #1507
Closes #1509
test(carousel): removing stale code

Closes #1502
demo(all): add bower link to download modal

Closes #1515
chore(tests): run tests on IE10
chore(tests): run tests on IE11
docs(typeahead): correct gramatical errors
docs(index): clarify Bootstrap CSS compatibility

Closes #1519
fix(modal): support close animation

Tests now have to wait for animation before checking for open modals.
Tests should actually check for the 'in' class.

Setting up both the transition end handler and a timeout ensures that
the modal is always closed even if there was an issue with the
transition. This was the implementation used by Twitter Bootstrap modal
JS code.

Note that unbinding the transition end event within the event
handler isn't necessary, and, worse is currently buggy in jqLite (see
https://github.com/angular/angular.js/pull/5109 ).

Note that the scope is already destroyed when the dom is removed so the
$destroy call isn't needed.

Closes #1341