remove most commonly used git commands from help, just show release once, but copyright everywhere
be consistent no >> for any code snippets
move parseCMD, filterOpts to private/

* new style help in private/jgit_help shows synopsis consistent with man
 pages, but only available jgit commands.
* show version and call update to download latest jar
* show available commands for jgit help
replace version 0.5 ... with copyright
cmd in alphabetical order
add ADD and CHECKOUT help, clean up, add set-update option to checkout and simplify checkout path
fix java thinks pwd is matlab userpath, ha
add clone args, opts & help to jgit