Ensure types other than float/int32 are supported

[ftynse]

• [x] teach parser about bool, int8, int16, int32, int64, float16, float64
• [x] make sure Halide types are properly constructed
• [ ] make sure polyhedral dependence analysis behaves correctly for complex types
• [x] teach memory promoter about byte-sizes of each type (@ftynse)
• [x] write tests involving all types

[nicolasvasilache]

Great, thanks!

[ftynse]

Actually, memory promotion takes the byte-size from Halide, so it should just work. https://github.com/facebookresearch/TensorComprehensions/blob/f5e3899ddda03c378cc5ce2717e4f28eb92c70d8/src/core/polyhedral/memory_promotion_heuristic.cc#L431

[prigoyal]

yeah and the byte sizes information is also part of DLTensor