feat(rating): add rating directive

Closes #337
demo(typeahead): fix a link to the select directive
fix(dialog): IE8 fix to not set data() against text nodes

Closes #328
feat(position): add new positioning service
fix(typeahead): fix matches pop-up positioning issues

Closes #262, #282
fix(dialog): close dialog on location change

Closes #335
fix($dialog): fix $apply in progres on $location change
docs($dialog): add missing method isOpen in doc
fix($tooltip): fix positioning issues in tooltips and popovers

To calculate the relative position of the tooltip or popover, the
$tooltip service now uses the $position service, which resolves many
positioning bugs.

Closes #265, #115