WIP: API-doc
turned scaffolding into a dictionary
slightly refactored create_run
added named_configs feature
added optional prefix to capture and command
Merge branch 'develop' into release/0.5

Conflicts:
	sacred/experiment.py
added documentation for the new features
Merge branch 'release/0.5' of https://github.com/Qwlouse/sperment into release/0.5