Flexible, customizable windowed-adaptation for learning HMC metric
Increase default warmup iterarions
Merge branch 'develop' into feature/flexible_adaptation
Merge branch 'develop' into feature/flexible_adaptation
Updated doc, default target acceptance prob
Update docs and args with more informative  names and descriptions
Merge branch 'feature/flexible_adaptation' of github.com:stan-dev/stan into feature/flexible_adaptation
Tweaked adaptation text
Merge branch 'develop' into feature/flexible_adaptation

Conflicts:
	src/stan/gm/command.hpp
Merge branch 'develop' into feature/flexible_adaptation
Tweak timing of index increment, update tests
Merge pull request #356 from stan-dev/feature/flexible_adaptation

Feature/flexible adaptation