Fix json_term()
Update README [ci skip]
Change Body spec and remove 'json' keyword from Headers
Update CHANGELOG, README, docs/types.md
Update docs/callbacks.md
Make ct-suites beauty
Put erlang.mk inside Makefile
Bump 0.1.2
Update leptus_handler:reply/6
Merge master into msgpack & add a test-case for replying with msgpack