Added hook to allow makeflow to specify WQ activate worker waiting.
Updated names for long opt.
Fixed race condition between simultaneous parrots creating the cache directory.  Check for the case where mkdir fails because the directory already exists.
Use mkdir rather than create_dir for subdirectories, to avoid n^2
traversal of the directory hierarchy.
Merge branch 'dthain-master'

This fixes a race condition in the creation of the parrot cache directory, by
treating mkdir returning EEXIST as a success rather than a failure. This might
solve a problem reported by Matthias Wolf re CMS jobs run on multi-slot
workers.
Merge branch 'mf_wq_wait_hook' of git://github.com/nhazekam/cctools into nhazekam-mf_wq_wait_hook

Just quick update to allow makeflow to take advantage of WQ's functionality
that waits until x amount of workers are connect to disperse jobs