Add custom size_of trait
Make tinfl_put_buf_func_ptr publicly visible
Make enums into const for type purposes
Combine all compression flags
Make all memory constants `const`
Mutability fix in adler32
Use tinfl_decompressor impl
Type, safety, lifetime, and mutability fixes for decompression
Minor comment changes
Significant type & unsafety fixes for compression

This also fully Rustifies the public interface for compression, and
uses the CompressionFlags enum.