ArkCargo v0.2.3 for EMC Isilon oneFS 7.1.x

Adds:
a bugfix for a MemoryError,
improved identification of symlinks that point to directories,
added capability to stop a job such that is can be restarted again

ArkCargo v0.2.1 for EMC Isilon oneFS 7.1.x

minor fixes releasing 0.2.1