if you run on python2.4 it should fails with an error message

like before the refactoting if you run with python 2.4 and you try
dynamic tracing it will write an error message explaining the
problem
stupid typo in blotter __init__
use self.swirl.getDependencies in checkHash
dynamic tracing: trace environment variable for each binary
sergeant: user env and rpath when verifying swirl

When we verify a swirl we now use the rpath and env variables
used at run time by each binary
composer: verify file existence before trying to archive it