Removing unused md5 comparison

Adding formatting to CXX progress reporting to test to match others

Change-Id: Ia58ae102a266e3a9f7528b0726f1447403f5b1c7
Adding PyCommand to be used with any python callable

This adds support for one-line add commands with python lambdas. The
PyCommand changes the access to the OwnedByProcessMethods to
facilitate the custom AddCommand method.

Change-Id: Ia70ad36e0b4e0545d5d2b8547fe04d8b7739ba7f
Merge topic 'SIMPLEITK-463_AddPyCommandSupportForCommands' into next

4fc57a32 Adding PyCommand to be used with any python callable
5ee17471 Removing unused md5 comparison