Added /g lock system, commands and features:

/g lock
Locks container/block (chest, door etc.) player is facing within your groups claims

/g lockinfo
Shows information of locked container/block player is facing

/g lockadd <Player>
Adds player from your group or allied group to own lock player is facing within your groups claim

/g lockremove <Player> Removes player from your group or allied group to own lock player is facing

Functions
Locked containers/blocks are immune to griefing
Lock override access goes in order of seniority (e.g. Leader can access/unlock moderator and member locks, members cannot access/unlock moderators locks)
Tab complete now works for offline players when using lock system
Removes players from all group and/or ally groups locks if they are kicked or leave their current group
Removes locks in groups claims if group is deleted
Doors that break as a result of their support block breaking have locks removed