thcrap: tell jansson to use the malloc/free from our CRT
thcrap: tell jansson to use the malloc/free from our CRT

Some jansson functions require the caller to free() the result.
And, for some reason, jansson doesn't seem to be using the same
malloc/free functions than thcrap, so the free done by thcrap
doesn't match with the malloc done by jansson.

thpatch/thcrap,thpatch/thcrap,thpatch/thcrap,thpatch/thcrap,thpatch/thcrap