feat(uiView) autoscroll attribute

Adds an `autoscroll="expr"` attribute to `uiView` just like
`ngInclude` has, with the difference that if the `autoscroll`
attribute isn't defined then the scroll will happen in order to not
break the current behavior.
fix(uiView): it should autoscroll when expr is missing.
feat(uiView): cache and test autoscroll expression

Changes to follow ngInclude's behavior more closely (like #714):

- memorizes the autoscroll expression, since it's not supposed to be
  changed once the template is compiled, only the evaluated
  expression should change;
- the page won't autoscroll when the attribute isn't present, which
  is a breaking change from the current implementation.
feat(uiView): merge autoscroll expression test.
feat(uiScrollView) scroll page when ui-view is loaded

Replaces `$anchorScroll` call in `uiView` with a custom provider
which scrolls the element attached to `uiView` into the current
view instead. This should allow a finer default for designer by
scrolling automatically to the activate `uiView` without
manipulating anchors.

Calling `$uiViewScrollProvider.useAnchorScroll()` will restore the
current behavior or calling `$anchorScroll` instead.
feat(uiScrollView) typo in documentation
Merge pull request #715 from ysbaddaden/issue-110

feat(uiView) autoscroll attribute