TS now requires Sphinx 2.0.5 or better, so let's include the Riddle tweaks accordingly.

Closes #618.
Merge pull request #619 from weetu/master

Do not clobber :select option in facet search
Adding search_for_ids on scoped calls. Closes #628.
Custom middleware and mask options now function correctly with Model-scoped searches.
Connection failures have their own custom error class: ThinkingSphinx::ConnectionError.

Closes #614.
Always using DISTINCT in group concatenation.

Closes #603.
Don't use Sphinx ordering if SQL order option is supplied to a search.
Merge remote-tracking branch 'upstream/master'
Fix ThinkingSphinx::ActiveRecord::SQLSource#delta_processor spec to pass with delta_options
Added a new test in ThinkingSphinx::ActiveRecord::SQLSource#delta_processor spec to test delta_options
Fix utf8 weirdness on tests

Fixes #629
Merge pull request #631 from pedrocunha/fix-for-failing-sphinx-tests

Fix utf8 weirdness on tests
Separating real-time directory preparation from data generation.
Merge remote-tracking branch 'origin/master'
Don't presume the tmp directory exists.
Mysql2::Error is wrapped in ThinkingSphinx::ConnectionError.

No point ignoring Mysql2::Error if they're now raised as ThinkingSphinx::ConnectionError exceptions.
Cast every column for timestamp attributes with multiple columns.
Switch to SphinxQL functions for Sphinx 2.1.x.

To enable this behaviour, put the following in an initialiser:

    ThinkingSphinx::SphinxQL.functions!

This will become the default behaviour in Thinking Sphinx 3.1, though switching back will remain possible:

    ThinkingSphinx::SphinxQL.variables!
UTF8 setting for disabling forced encodings.

Sphinx 2.1.2 now returns UTF-8 strings for us automatically, which is excellent. If you're using 2.1.2, you should add the following to an initialiser:

    ThinkingSphinx::Middlewares::DEFAULT.delete ThinkingSphinx::Middlewares::UTF8

And also set utf8 for each appropriate environment in config/thinking_sphinx.yml to true.

This will become the default behaviour in Thinking Sphinx 3.1.
New search options in Sphinx 2.1.x.