Update HelloAndroid for more recent Android SDK
If a buffer is not written to and is accessed uniformly w.r.t. thread indices, put it in constant memory.
Merge branch 'master' into gpu_constant_memory
Moved GPU constant memory queries to CodeGen_GPU_Dev
Added small sample app for testing OpenGL functionality on Android
Changes to OpenGL backend to enable basic functionality on Android
Merge branch 'master' into opengl-android
Removed unused files
Fix name mangling for GLSL

Identifiers containing "__" *anywhere* are reserved in GLSL. Turns out that
Android's OpenGL implementation enforces this...
Added size of static images to buffers captured in a closure.
Generated kernel code build options.
Added GPU_Argument which passes the known size of buffers to the GPU device code generators, implemented constant memory more robustly for OpenCL C.
Merge branch 'master' into gpu_constant_memory
Replaced std::pair with struct.
Fixed address spaces for __constant buffers.
Added test that uses a constant generated Func (should map to constant memory in GPU targets).
Added tests for generated and multiple constant funcs in GPU pipelines.
Merge branch 'gpu_constant_memory' of https://github.com/halide/Halide into gpu_constant_memory

Conflicts:
	test/correctness/convolution_generated_kernel.cpp
Fixed tabs -> spaces.
Added operator < to BufferSize, removed equivalent functor predicate.