Add enforcement of @Console, update dependencies, bump version to 0.4.1-SNAPSHOT

The ```@Console``` annotation was previously not enforced (allowing the console to execute commands not annotated with ```@Console```), so I added a check in the Bukkit module. I also updated some dependencies, and bumped the version to 0.4.1-SNAPSHOT, to represent the fix.

(Note: I'm not sure why I re-committed @Anxuiz's commit, and I don't know how to un-do that.)