Compatibility changes for Cement 2.1, global scope

Various changes to accomodate Cement 2.1.  Using hooks for registry
loading and scope setting.  Fixing various scoping corner cases.
Merge branch 'master' into feature/integrate-scope

Conflicts:
	nepho/cli/base.py
Merge pull request #139 from huit/feature/integrate-scope

Rewritten scope functionality should work with all the various corner cases