Added getEvaluationByName, check for access rights in Submit(), and fetching of files from submissions.
Integrated changes from https://github.com/Sage-Bionetworks/synapsePythonClient/pull/68/ due to overlapping fixes.
Merge pull request #72 from kaysoky/submissionAccessAndConfirmation

Added getEvaluationByName, check for access rights in Submit(), and fetc...