Add nginx reverse proxy to apache in Vagrant VM

Accessible at port 9001.
Add gunicorn to Vagrant VM
Automatically start dev server in Vagrant VM
Docs: Explain changes to Vagrant VM
Filter by date range in Dasboard/Reporting, if provided
Filter different reports properly
Fix custom_range bugs with ugettext_lazy in custom range object name,
and unique fields error when creating existing custom ranges.
Fix for delegate of num_products to a proxy class as documented.
Fix issue with updating basket cookie in the middleware

Handle the case correctly where the basket cookie needs to be deleted
and updated in the same request. This can happen when unfreezing the 
basket. Django's response.delete_cookie doesn't remove the cookie from
request.COOKIES so we need to manually check this.
Merge remote-tracking branch 'upstream/master' into fix-basket-cookie

Conflicts:
	oscar/apps/basket/middleware.py
Made entire phrases translatable rather than individual words in the Dashboard index page.
Merge pull request #1098 from itbabu/dashboard-index-page-translations

Made entire phrases translatable rather than individual words
Correct chdir path in uWSGI conf
Use correct currency for voucher order totals
Correct template logic for showing "no categories" sentence
Ensure postcode validation error renders correctly in Django 1.6
Avoid AttributeError for abstract model docstrings
Add checkout sections to release notes
Adjust manifest file since there isn't any more JSON with oscar/apps/
Made strings in OrderSearchForm.description translateable.

This basically removes the code level concatenation of sentence parts
that make it impossible to translate this properly.

Fixes #1100.