split mask mode functions.
Add stacked mask mode to Incremental, Markov and Wordlist modes.
It's not actually handled in mask.c yet. Also, resuming a stacked
session may (or may not) need work.
Hybrid-mask enabled.
GPU: Initialization tweak and other minor fixes.
Benchmark: Print GPU utilization (if available) after benchmarking
OpenCL or CUDA formats more than one second.
In hybrid mask mode, do not use candidate alone. While it could
sometimes be a feature, it could also produce up to 50% unwanted
candidates.
Bug fix for hybrid Markov + Mask mode.
Optimization for short masks: Avoid repeated strlen's that the
optimizer would not dare taking away as written. Also make key
a const char* so we don't screw up.
Bugfix for non-hybrid mask mode.
Bugfix for hybrid mask w/ node/fork: For now we always let the
parent mode distribute the work. For large masks it might be
better to let mask distribute but that is a more intrusive
change (to all modes).
Merge pull request #821 from magnumripper/hybrid-mask

Hybrid mask
Fix non-GPU builds for bug introduced by 9a5e3ae