Fix asset path of arial GPB for Android in sample04.
pre-compiled armv7s lib for bullet, png, lua and oggvorbis
Merge pull request #778 from kwhatmough/master

Fix asset path for Android too.
libpng 1.4.8
Merge pull request #780 from mozeal/master

libpng 1.4.8
Merge pull request #783 from blackberry/master

Rebase master to next