Some changes to use PEP8 conventions.
1. Refactor test and dataset parameter definition.
2. Inclusion of num_repetitions as a test parameter.
1. Modify imports to include the whole path.
1. Change imports to deal with different versions of Python (2 and 3).
1. copy_history copies all the files to a flat directory (intermediate directories are removed).
2. copy_history allows the user to specify a list of job_ids to be copied.
1. Add success attribute to job.
2. Refactor jar_job calling in hg5k.
1. Rename scripts to remove .py extension.