fix for connection pooling.

by defining these methods in the adapter class, we prevent calls from the ConnectionPool class being proxied to the master connection. this allows pool checkouts/checkins to work as expected without interacting with the master/slave connections.
Rails 4 support
Make instructions about errors during startup more explicit.
Hook into rails db:* tasks load_config so seamless_database_pool can remove itself for tasks that are based on the adapter name.
Merge branch 'master' of https://github.com/red5studios/seamless_database_pool into red5studios-master
Merge branch 'rails4' of https://github.com/mobi/seamless_database_pool into mobi-rails4
Update connection adapter specs to use mysql2 gem instead of old mysql gem.
update history and version number
Add class name to dynamically generated connection adapter for compatibility with code that looks at the name.
Regenerate gemspec for version 1.0.13
Fix to work with query cache.

End support for ActiveRecord 2.x

Add support for ActiveRecord 4.0
Make driver less aggressive about overriding methods to proxy to the master connection.
remove ruby connection timeouts in favor of socket timeouts
get rid of connection timeout logic
update history
update gemspec
bump version
update specs; support ActiveRecord 4.1 configurations; improved to_s on connections
Regenerate gemspec for version 1.0.15
Use the connection.to_s output for connection.inspect