GridLayout needs to call measure on children after it knows how large children should be

Also:

. Remove deprecated methods and XML attributes.
. Stop Spaces having margins by default.
. Remove getSpacers() and findUsed()
. Change default for row/columnOrderPreserved() from false to true.
. Improve automatic index allocation mechanism to use individual maxima.

Change-Id: Id79fbb2e70a0bf2002191ec2a9746547d896de72