Rename cinema_store class to CinemaStore.

Making class naming consistent with style.
Updating cinema_store/explorers APIs

Refactoring cinema_store/explorers APIs.

Updated test_pv_slice() in tests.py to use the new API.
Update vtk_explorers to use the new API.
Merge remote-tracking branch 'dave-github/master' into api-updates

* dave-github/master:
  rename UpdatePipeline to Run and demonstrate an idea
  flesh out the paraview adapter's color engine
  add a contour and a templated pv explorer

Conflicts:
	explorers.py
	pv_explorers.py
	tests.py
Updating all new code after merge to use the newer API
Added basic find() support to Store.
Remove obsolete code.
Added ability to execute a single document.
Added documentation.
Merge pull request #9 from utkarshayachit/api-updates

bring in refactored database layer

the storage layer is swappable. it is now straightforward to replace 'file' with an actual database interface
the storage layer is searchable and uses familiar database terminology