Merge branch 'release/0.5.1'
db: Limit the size of autocomplete tables

Impose a 1000 row limit on the number of autocomplete suggestions.

Issue #316.
db: Use text frequencies to determine ac suggestions

Issue #316.
db: Refactor autocomplete logic for cleanliness

Issue #316.
Merge branch 'issue/316'
db: Filter propert-words list

Issue #314.
Merge branch 'issue/314'
Bump release version for '0.5.2'
Merge branch 'release/0.5.2' into stable