Add tests for configuration methods

This commit also includes fix for configuration methods of DataMapper and MongoMapper collection. Closes #280.
Add maintainers under spec.authors
Changes for 0.15.0
:scissors:
Add CHANGELOG for safe defaults
Remove coveralls, fixes #476

"it doesn't fit for us" -matsuda-sama
Version 0.15.0
Rename CHANGELOG to CHANGELOG.rdoc
remove .coveralls.yml

Follow up for 6af7e529632ce7f922ce5aeae0584032809831cd
Merge pull request #478 from mrfoto/patch-1

Rename CHANGELOG to CHANGELOG.rdoc
Merge pull request #479 from eitoball/remove_coveralls_yml

Remove .coveralls.yml
Tweak @options before use
Reduce Hash creation
rbx-19mode  =>  rbx-2.1.1
Seems like we'd better not expect the rbx tests to pass...
kaminari doesn't have to always depend on sqlite3

bundle sqlite3 only under AR and DM
Use activerecord-jdbcsqlite3-adapter gem under jruby
CI against jruby
Resolve tzinfo version conflict
Allow another AR-edge failure