* Sort results by the name
* Switch search method to simple `LIKE` matching instead of tsvector/tsquery

Previously we used scores from ts_rank_cd() to sort results, but it didn't work
because the function returns same score for all results. It's not for calculate
similarity of single words. Sometimes this bug even push out exact matching tag
from results.

Additionally, PostgreSQL supports prefix searching with standard btree index.
Using it offers simpler code, but also less index size and some speed.

* Clean up SQL output in Tag and Account search methods

* Add basic coverage for Tag.search_for

* Add coverage for Account.search_for

* Add coverage for Account.advanced_search_for

Fix anchor tags in some wikipedia URLs being matches as a hashtag