Show 'synonymous' instead of all non canonical tags

Noncanonical tags encompass both unfilterable and synonyms.

There was already a column to show unfilterable tags only.

The 'noncanonical' column was showing unfilterables and tags that had been merged with synonyms (mergers).

Now there is a 'synonymous' column instead, which shows only non-canonical tags that have synonyms.
When sorting by taggings count, also provide secondary sorting by name

Taggings count don't provide enough order - when too many tags have the same number of uses, the results of sorting are unpredictable and the order keeps changing.

This adds secondary sorting by name, ascending, when the taggings count is the same.
3652 unclosed HTML tag on user signup page
3620 mention podfic in inspired by field on new work form
3761 Caution for draft page warning
Merge branch 'refs/heads/master' into issue-1891-view-synonyms-only
Merge branch 'refs/heads/master' into issue-3278-sorting-taggings-count
Merge branch 'refs/heads/master' into issue-1891-view-synonyms-only
Merge branch 'refs/heads/master' into issue-3278-sorting-taggings-count
Issue 3285:  Include the site name in the sender field of notification emails
Fixing mailer issues
More rebase nonsense
Added tests
Created specs for the mailers
Merge pull request #1330 from sarken/issue_3761

3761 Caution class for draft page warning
Merge pull request #1247 from sarken/issue_3620

3620 mention podfic in inspired by field on new work form
Merge pull request #1246 from sarken/issue_3652

3652 unclosed HTML tag on user's signup page
Update to newest version of FactoryGirl syntax
Fixing collection mailer spec
Merge pull request #862 from scottsds/issue_3285

Issue 3285:  Include the site name in the sender field of notification e...