Plenty of changes to ease adding new REPL commands

*Added wrapper classes for encompassing command calls, invocations, and usages
*Corrected file path tab-completion (with correct ordering of arguments)
*Added column-based output formatting
*Added "history" command
*Added "save" command to serialize cluster state to disk
*Added main plumbing for "load" command to load cluster state from archive off of disk
Fixing log4j shenanigans
Fixing log4j shenanigans [part deux]