Fix test failures due to shoulda not finding 'assert_hits_per_views' method.
Fixed deprecation warning from requiring 'active_support/core_ext/logger'
Add support for optional random seeds (closes #21).

1. MySQL supports seeded RANDOM()
2. Postgres supports seeded random via SELECT SETSEED()
3. SQLite does not support seededing, so we approximate it by hashing the
   id column with the seed.
Merge pull request #22 from curious/random-seeds

Random seed support