Add VisTrails ModuleSuspended support to current 1.1

Follows Colin's original version on SAHM_1_1_moduleSuspended but that
merge had some issues (merge-base seemed wrong) so this rewrites it
directly off the current 1.1 branch.
Fixed default value for BoostedRegressionTree.Alpha.

Actual values will be allowed in future versions of VisTrails, but
currently, you're limited to the serialized value as a string.
Use a hash -> dirname map to better support jobs run in loops.

Creates a vt_hashmap.dat file in the session directory that is used to
link the signature (computed in Module.compute) with the directory
name (e.g. "brt_1").
Merge branch 'SAHM_1_1' into module_suspended

Conflicts:
	init.py
	utils.py
Added a function to SpatialUtilities
that averages a list of rasters.
These rasters must already be the same
cell size, extents, projection, etc.
Allow multiple RastersWithPARCInfoCSV
inputs to PARC
Converted the PARC function
to Shrink extent to instead
pad smaller inputs with nodata.
Update import locations to match VisTrails 2.1
Merge branch 'module_suspended' into SAHM_1_2

Conflicts:
	init.py
Cleanup of unused files
Code formating cleanup
misc code formating cleanup
removed run monitor app