Update travis badge on README
Whitespace fixes on the Gemfile
Remove unused variables

Usage of `adapter` variable was removed in: b39c8c9
Remove duplicated lines in Gemfile.lock
Load MysqlAdapter and Mysql2Adapter before trying to include our AbstractMysqlAdapter into them
Merge pull request #302 from vrinek/fix-travis

Fix specs
Merge branch 'master' into pre_count_on_sequel
Merge branch 'master' into pre_count_on_sequel