Add support for vectorized types

[wcmjunior]

Vectorized types like int2, int4, short2, short4, float2 and float4 should be supported by the compiler. Byte and char types, as well as its vectorized types byte2, byte4, char2 and char4, should also be supported.
This implementation is quite simple, once it will afect only a few places in code. The array base test class must be extended for both RS and PM runtimes in order to validate this implementation.