Expose StaticLayout.Builder publicly

Expose the new Builder pattern for creating StaticLayout. This allows
access to a number of features that have been available to TextView
through a hidden constructor. Some of these features have existed
for a while (mostly maxLines), while others are new (breakStrategy,
indents).

The builder is cleaner and has a better upgrade path than the old
pattern of lots of constructors with varying numbers of arguments.

Bug: 20190561
Change-Id: Ia3cd124825ab0cb469d22d1fc576ad26454545b8