fixed issue #12 -> Job-Meta-Data will now be pulled from star exec. If job is completed, all results will be inserted into the db, otherwise the results will always(!) be pulled from star exec, until the job is completed
sadly: currently all completed jobs on star exec seem to have the status "paused"

implemented Session-Caching via "~/.star_exec_session"-File in Home-Directory (could cause problems with multiple running Yesod-Apps, as they all read and write the same file) -> should be considered as "to be tested"