[#1253] Move user guides from the wiki to the repository
[#1253] Remove contents block and fix warning on the sysadmin guide
[#1253] Get images into our repository, instead of Flickr
[#1253] Fixing licence -> license to follow US English
[#1253] Change the titles to comply to our docs' guidelines
[#1253] Change "Organization" capitalization to comply with our guidelines
[#1253] Add text about the user/sysadmin guides on the index page.
[#1253] De-indent lists in the user guide.
[#1253] Remove redundancy and cross-link "Getting Started" and "Sysadmin Guide"
[#1253] Fix a few section titles' capitalization
[#1298] Fix activity and about organization pages

The controller methods didn't use `self._action` which will use the
appropiate `group_` or `organization_` action depending on the group
type.

The `organization_activity_list_html` action hadn't been used at all
until now, as there was a syntax error.
[#1304] Clear and keep current database during test runs

Add option '--reset-db' to drop and reinitialize database during test
runs
[#1304] change clean_db to rebuild_db in new_test/helpers.py

Otherwise new_tests will drop and recreate database
[#1304] update docs on 'reset-db' test option
[#1304] make sure database is rebuilt during travis test runs
[#877] First cut of adding Nginx instructions
Merge origin/master
Rebuild main.css
Merge remote-tracking branch 'origin/master' into 1304-reset-db
Merge pull request #1304 from okfn/1304-reset-db

'--reset-db' option for when running tests