Fix incorrect void * in generated _as_root JSON parsers (#73)
Fix incorrect void * in generated _as_root JSON parsers (#73)

* Add to '(char*)buf' when calling flatcc_json_parser_table_as_root in generated code, to support compiling the json_parser header with a C++ compiler

* Replace 3rd parameter type to generated '%s_parse_json_as_root' by '(const char*)'

dvidelabs/flatcc,dvidelabs/flatcc,dvidelabs/flatcc