Added threaded parallel file searcher class.

File discovery in large image directories is slow, in particular because
we need to stat() every file we find in a recursive traversal.  This class
provides support for threaded parallel calls to identify files and extract
their metadata.
handle unreadable files and missing links
initial commit of cellprofiler using subimager
wrap filefinder in tree checkbox dialog
subimager client can save / uses new protocol. Added paeth filter to cython code in _filter
Client uses deadman switch + new .jar
Added tests for client + start of OME parsing
Added omexml parsing classes + tests
Initial edits to handle image plane portion of pipeline
Merge branch 'master' into file_ui
Images module with filter and file tree viewer / pipeline has an image plane descriptor section
Merge branch 'subimager' of github.com:LeeKamentsky/CellProfiler into file_ui
Merge branch 'master' into file_ui
change back to standard TreeCtrl, add Queue.Queue to handle updates from file finder thread
Merge branch 'parallel-file-searcher' into file_ui
Add logger configuration, make start_subimager threadsafe, clean up subprocess output logging.
Start of metadata collection & parsing
Merge remote branch 'origin/file_ui' into file_ui
Get planar images within image stacks
Lots and lots of filters