Merge pull request #530 from kanoi/master

drillbit format %z not valid on windows
Reinstate work utility based hashmeter for knc.
Fix trivial warnings in knc driver.
Merge pull request #531 from kanoi/master

drillbit asic - enable in api.c
Merge branch 'master' of github.com:ckolivas/cgminer
Update NEWS
Bump version to 3.9.0