klondike - display MHz also
Klondike - extra zero value and range checking in temp conversion
Klondike - increase circular read buffer size
Merge pull request #502 from kanoi/master

Klondike temp checking and read buffer size
Convert all usb control transfers to asynchronous communication with our own timeout management as well.
Merge branch 'master' of github.com:ckolivas/cgminer
Merge branch 'master' into libusbx
Add a hash_driver_work function to allow for drivers that wish to do their own work queueing and management.
Convert the bitfury driver to use the hash_driver_work version of hash_work.
Provide a lower level __bin2hex function that does not allocate memory itself.
Use stack memory in test_work_current, avoiding a malloc/free cycle each time.
Use stack memory for hex used in stratum share submissions.
Use a timeout with usb handle events set to a nominal 200ms and wait for the polling thread to shut down before deinitialising libusb.
Although async transfers are meant to use heap memory, we never return before the transfer function has completed so stack memory will suffice for control transfers, fixing a memory leak in the process.
Do not perform bfi int patching for opencl1.2 or later.
Free a libusb transfer after we have finished using it to avoid a dereference in usb_control_transfer
Use a write lock when performing any USB control transfers to prevent concurrent transfers.
Merge branch 'master' into libusbx