Drop an nvidia workaround that just affect 9600GT on 295.49. If needed, we
must make the selection criteria more narrow because it makes krb5pa-sha1
fail on Bull.
gpg-opencl: Honour LWS and GWS environmental variables.
Merge pull request #164 from claudioandre/unstable-jumbo

Important fixes for now.
strip-opencl: Honour LWS and GWS environmental variables.
xsha512-opencl: Honour LWS and GWS environmental variables.
keychain-opencl: Honour LWS and GWS environmental variables.
nt-opencl: Honour LWS and GWS environmental variables, plus optimizations.
pwsafe-opencl: Honour LWS and GWS environmental variables.
raw-sha512-opencl: Honour LWS and GWS environmental variables.
Ignore environment LWS in common find_best_workgroup. Formats that handle
that won't call this anyway.
Fix a minor bug in nt-opencl: This format does not honour the count
argument to crypt_all() so we better set min_keys_per_crypt same as max.
phpass-opencl: Honour LWS and GWS environmental variables.
mysql-sha1-opencl: LWS/GWS (environment variables) fixes.
Ensure local/global_work_size are reset in all OpenCL formats. When running
--test, we may otherwise end up using figures from a previous format.
raw-sha1-opencl: LWS/GWS (environment variable) fixes.
Final fix to the SIGALRM problem. My previous attempt at installing a restarting
signal handler was correct but incomplete (only worked on some platforms).
Office OpenCL formats: Once again revert to using scalar code for all devices
due to what seem to be driver bugs.
Rename CL_VERSION_1_0 macro to HAVE_OPENCL to clean the code a bit.
Common-opencl: do not release unused event. No harm done but it can produce
confusing debug messages.
Wpapsk-opencl, krb5pa-sha1-opencl: Faster LWS enumeration (no iterations).
Bugfixes for the new restart code in bench_handle_timer().