android host reorg

[halfnelson]

• This changes the android host to import gradle files from src folder. It factors out the common settings to the main gradle project that gets created with moaiutil host create android-gradle
• It needs the ndk to perform a final link of all the libs that are included in host_config.h and all the android host modules specified in the gradle.properties file
• it also fixes a small build problem in ios builds from cmake
• Remove forced UINT for vertex render so that opengles 2 implementations that don't have the opengl extension can work. This means the code now runs correctly on the android simulators.