icarus: Defer initial open until init
icarus: probe_timeout setting to control how long we wait before giving up on probes
Rename icarus-common.h to driver-icarus.h
Merge branch 'icarus_cfg_detecttimeout' (early part) into bfgminer

Conflicts:
	driver-icarus.c
Merge branch 'icarus_cfg_detecttimeout' into bfgminer