Make old rapidsms pagination "digg-style" pagination

Show pages around current page in pagination.
Update paginator template to be use bootstrap
Don't show extra pages (border or adjacent) when there aren't items there.
Remove href tags from disabled links.
Fill in gaps of 1 page with missing page not elipsis.
Tests for paginator
Remove vim header
Fix set syntax for python <2.7
Refs #326: Optimize queries in registration and message log

- registration: use prefetch_related so each contact's connections
  are pre-fetched and we don't need one query for every contact on
  the screen
- messagelog: use select_related to include each message's contact,
  connection, and connection backend in the original query, so we
  don't query for them for every message on the screen

Branch: 326-optimize-queries
Merge pull request #326 from rapidsms/326-optimize-queries

Speed test with Django debug toolbar
Disable Next button on last page.
Clean up variable names.  Remove now unused context variables.
Remove unused import
Paginator tag documentation
Merge 297-pagination. Fixes #297
Merge branch 'release-0.12.0' of https://github.com/rapidsms/rapidsms into release-0.12.0
Bootstrapify buttons in rapidsms.contrib.registration
Fix pagination test

- Add template context processor for request to test settings,
as paginator tag assumes request will be in the context.
- Add a check in the paginator module for that setting, so folks
will get a useful error if they don't have that processor
configured.
Remove `under development` warning from 0.12.0 release notes
Point at .12 version of project template

In the instructions for installing from the project template, update
the URL to install using the release-0.12.0 version of the template.
Removed extraneous stylesheet