#372: Make "update available" button in admin bar

Conflicts:
	tendenci/apps/dashboard/templates/dashboard/index.html
	tendenci/core/base/urls.py
	tendenci/core/base/views.py
#372: fixes to tendenci update
#372: Fixes for server restart
#372: Updates on 'update tendenci' page

Conflicts:
	tendenci/core/base/urls.py
	tendenci/core/base/views.py
#372: Changes and fixes

Conflicts:
	tendenci/core/base/managers.py
	tendenci/core/base/urls.py
	tendenci/core/base/views.py
#372: Tried using a different approach in catching if the update is done.
#372: Added cleanup and fixes
#372: fixes
#372: Added call to clear cache command after update
Removing "Update Tendenci" link, more testing required.