Minor fixes to animation ApiDemos

Many of the original animation demos still had hardwareAccelerated="false"
in their activity tag. This was originally necessary due to the state of the
hw renderer in 3.0, but is no longer necessary.

Also, added documentation to the new Transitions demo.

Issue #7902583 Update animation ApiDemos to use hw acceleration

Change-Id: I7add3acc10d8fa36648e1869a3ec91088b2e199d
2 files changed