Refs #269: Make page footer fixed

We want the page footer to be pushed down to the bottom on short
pages, and appear normally after the content on longer pages.

Had to rearrange the html a bit to get this all working with
bootstrap and responsive.

Branch: feature/269-footer-at-bottom
Refs #269: Merge remote-tracking branch 'remotes/origin/release-0.12.0' into feature/269-footer-at-bottom

Conflicts:
	rapidsms/templates/layout.html

Branch: feature/269-footer-at-bottom
Refs #269: Bump copyright in page footer to 2013
Branch: feature/269-footer-at-bottom
Remove contrib.export app.

Fixes #196
Merge remote-tracking branch 'remotes/origin/feature/269-footer-at-bottom' into feature/268-remove-rapidsms-tabs

Branch: feature/268-remove-rapidsms-tabs
Refs #268: Remove RAPIDSMS_TABS

Get rid of RAPIDSMS_TABS setting and the template tag that used it.

Instead include the template "rapidsms/_nav_bar.html" at that point
in layout.html, provide a sample file with commented example links.

Branch: feature/268-remove-rapidsms-tabs
Remove contrib.ajax (#217) and contrib.scheduler (#282)

Remove these two contrib apps.

Branch: 217-282-remove-contrib-ajax-and-scheduler
Freshen AUTHORS file
Branch: release-0.12.0
Fix EmptyPage exception

Messagelog was throwing an EmptyPage exception when rendering its table using djangotables2.

Changed template to not try to generate a link to previous or next page when there's not one.

Branch: fix/emptypage-exception
Merge pull request #281 from rapidsms/remove-contrib-export

Remove contrib.export app.
Merge pull request #283 from rapidsms/217-282-remove-contrib-ajax-and-scheduler

Remove contrib.ajax (#217) and contrib.scheduler (#282)
Merge branch 'release-0.12.0' into fix/emptypage-exception

Branch: fix/emptypage-exception
Merge pull request #284 from rapidsms/fix/emptypage-exception

Fix EmptyPage exception
Merge remote-tracking branch 'remotes/origin/release-0.12.0' into feature/268-remove-rapidsms-tabs

Conflicts:
	rapidsms/templates/layout.html

Branch: feature/268-remove-rapidsms-tabs
Remove RAPIDSMS_TABS from tests/default.py
Branch: feature/268-remove-rapidsms-tabs
Start a doc page on how the frontend works. Document how to control the links at the top of each page.
Branch: feature/268-remove-rapidsms-tabs
Add a bit of padding above the footer, and a few comments
Branch: feature/268-remove-rapidsms-tabs
base.html and HTML5

- Change layout.html to base.html - fixes #275
- Make layout.html just extend base.html
- Change templates to extend base.html
- Add doc that layout.html is deprecated
- Change base.html to HTML5 - fixes #270
Branch: feature/275-base
Merge pull request #268 from rapidsms/feature/268-remove-rapidsms-tabs

Remove RAPIDSMS_TABS
Merge branch 'release-0.12.0' into feature/275-base

Branch: feature/275-base