Update the after_filter for auto-commit to be overridable on a per class basis.

[rgarver]

We have situations where a controller should avoid committing to Solr since the immediate availability of a document is not critical. The case we use this for is on API calls where we want to do the indexing inline (so we give some back-pressure on the caller) but the update doesn't need to be immediately available. These API calls happen frequently so reducing load on Solr is important.

This could be implemented with the auto_commit_after_request: false option, and then add the commit as an after_filter everywhere we want it, but this use case is a bit of an inversion of how auto_commit_after_request is best used.

[sdhull]

Generally good practice to have before_filter and after_filter be named methods, which allows developers to override or use skip_before_filter. 👍