bflsc - allow a 0 in DEVICES IN CHAIN
bflsc - also allow ' 0' in DEVICES IN CHAIN
Convert icarus driver to hash_driver_work model.
Set device_diff on work in get_work to not be missed with drivers that use get_work directly.
Make the USB polling thread poll every second to potentially aid longer timeout transfers.
Prevent further USB transfers from occurring once the shutdown signal has been sent to prevent transfers getting stuck and libusb failing to shut down.
Initial import of jansson-2.5
Update jansson to only build parts we require and suited to our build environment.
Fix open coded use of autoreconf in autogen
Add m4 directory to jansson
Work around older libtoolize that fails without top ltmain.sh not being present during autogen
Remove unused parts of libusb

Conflicts:
	compat/libusb-1.0/doc/Makefile.am
	compat/libusb-1.0/doc/doxygen.cfg.in
	compat/libusb-1.0/examples/Makefile.am
	compat/libusb-1.0/examples/dpfp.c
	compat/libusb-1.0/examples/dpfp_threaded.c
	compat/libusb-1.0/examples/hotplugtest.c
	compat/libusb-1.0/examples/listdevs.c
	compat/libusb-1.0/examples/sam3u_benchmark.c
Remove unused components of jansson
Update NEWS.
Bump version to 3.6.2
Revert to using timeouts on !linux since libusb leaks memory without them.
Speed up polling repeat again in usb poll thread and handle async after the message to disable polling is complete.
Optional lock tracking and stats via the API
API add 'MHS %ds' to 'summary'
Merge branch 'master' into mergelibusb