Replace funciton returning int instead of jsmnerr_t
When trying to compile the source code with the version 4.6.3 of GCC as C++ code, the compiler complains about conversion between int and jsmnerr_t.
Indeed, for several _parse functions, the return type is set to int whereas they always return one of the values of the jsmnerr_t type.
Replacing their return type by jsmnerr_t solves the issue.
Btw, nice tool. Thanks for sharing :-)