Replaced by dump_course_structure on lms

This reverts commit ec01253e, reversing
changes made to ae8c9710.

as a first step to separating db connection from modeling
and to support location mapper and contentstore using same db config as modulestore

Just works on the tabs list in mongo, nothing
deeper than that.
Added implementation functions in tabs.py,
providing a first step for some future
GUI editor.

refactor some code out of the django-admin entry point into a help function in CMS. Update tests to use new method

define a unseeding forums permissions and call into it from delete_course

define a unseeding forums permissions and call into it from delete_course

Conflicts:
	cms/djangoapps/contentstore/views/course.py
	common/lib/xmodule/xmodule/tests/test_combined_open_ended.py
	lms/envs/common.py

Inspired by: http://eldarion.com/blog/2013/02/14/entry-point-hook-django-projects/
Moves startup code to lms.startup and cms.startup, and calls the startup
methods in wsgi.py and manage.py for both projects.

change over the modulestore configuration to be a dict and use a property accessor. Also update some django-admin configs to use this means to set the runtime configuration

and without rewriting static links.  changes xml_importer.py and
import.py

add a metadata cache and re-compute ignore when deleting a course to speed up the whole thing as well as squelching warnings in the console output

add a new django-admin command to dump out a course structure document. This is response to an emergency request from Harvard researchers.

Instead, we use XModule field default values when creating an empty
XModule. Driven by this use case, we also allow for XModules to be
created in memory without being persisted to the database at all. This
necessitates a change to the Modulestore api, replacing clone_item with
create_draft and save_xmodule.

Includes unit tests and modifications to authz.py.

Also hooks up the granted and deny events to the course creator group.