removed do_ prefix from sizes images regions keys fxns, #2
removed dp_ prefix from droplets fxns, #2
updated calls to droplet fxns with new names
extracted common scp and ssh fxns, #6
moved some helper fxns to zzz file
added handler fxn to deal with missing scp and ssh tools on user machine #6
moved  all auth functionality to do_handle fxn, so out of all other fxns