REFACTOR Build armv7 and armv7s slices

TODO: Clean this script up, it's getting ugly.
Merge pull request #9 from wobbals/ios-armv7s

REFACTOR Build armv7 and armv7s slices
PATCH Use xcode's clang instead of google's prebuilt
Merge pull request #10 from wobbals/use-system-clang

PATCH Use xcode's clang instead of google's prebuilt
MODIFY android build script to default lightweight builds
Merge pull request #11 from wobbals/android-light

MODIFY android build script to default lightweight builds
Disable builld with libjingle
Merge pull request #1 from marinaserranomontes/fix_link_error

Fix link error