Compiler flags to disable features and shrink code size

[andrewwade]

It would be nice to have compiler flags to disable certain features. For example, I don't need parsing to write json logs. I'm only constructing the json and dumping it to strings but I like the convenience of how json objects are constructed in this library. I commented out the parsing stuff and reduced the code size by 60% so now I can put it on more embedded environments.

Possible features to turn off:

1. Parsing
2. SAX support
3. bson support
4. ubjson support
5. cbor support
6. msgpack support

[stale]

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