Illegal variable name 'type'

[ocramz]

Some FlatBuffers field names clash with Haskell reserved words, as in the Apache Arrow schema :

https://github.com/apache/arrow/blob/master/format/Schema.fbs#L471

The problem is that 'type' (and possibly others) are legal field names in FlatBuffers, but as of now this package re-uses the schema field names in the code generator without checking against a list of reserved Haskell keywords.

This test showcases this behaviour : https://app.travis-ci.com/github/dcastro/haskell-flatbuffers/builds/256468847#L8589