Store hashing algorithm in the metadata table

[nyurik]

Store hashing algorithm in the metadata table

[bdon]

faster fnv1a checksum algorithm

In tippecanoe we needed a content hash that had the smallest implementation to inline, unsure how the speed compares to md5, but if you need speed you'll probably want something like xxhash anyways.

[nyurik]

@bdon this proposal is to support and standardize all such algorithms, so that if tippecanoe created mbtiles file, other tools can validate it and possibly add more content, while using the same algo as the original