aapt now sorts the strings in the resource string pool.

In our current environment with very many translations, this can
save a lot of RAM -- for example over 200K in Gmail just by sorting
the strings in the Gmail .apk (not the framework).

Also add a new aapt command to print the contents of the resource
table string pool.

Change-Id: I1da037b3e2c377b890833ff57ab158965314ac48