Updated pom for building with java SDK 1.7

Seemed to be using 1.7 features anyways, not sure how this was
built with maven without setting this.
Added IDEA files to gitignore

Am I really the only one in the world that has embraced the wonders that is IDEA? How sad :(
Added SnakeYaml dependency to pom
Willie is now quite configurable :)
Can now specify if commands are only usable by admins.
Reload and join commands.
Admin and save commands.
admin command defaults to "admin list"
Leave command.
Admin authentication via nickserv and some minor corrections.
Merge pull request #5 from B2OJustin/configuration

Configuration, admin commands, leave/join commands, and more!