Add callback for user processing of json string and result of json scan.
Add explanitory comments to the new pdf_parse_string function
added cl_engine_set_clcb_file_props to libclamav map
added file_props_cb and data settings transfer
downgraded nullargs to json api from error to debug messages
Merge branch 'master' of git.clam.sourcefire.com:/var/lib/git/clamav-devel
Merge branch 'master' into always-on-json

Conflicts:
	libclamav/scanners.c
using master variant of json_api implementation