Also: All script tasks should raise WorkflowTaskExecExceptions - NOT APIExceptions - this is because our scripts are executed by Spiff (not the other way around) so the errors need to pass fluidly through spiff, and come back to use THEN we can convert them to APIErrors. Otherwise we lose all kinds of good information about the error.
Adding a DocumentService to clean up the FileService, and get Documents well seperated, as it seems likely be pulled out or seperated in the future, there is now a Documents api file as well, for the same reason.
Some other minor changes are just fixing white space to assure our code is linting correctly.
I removed _create_study_workflow_approvals from the base test, as we don't use approvals like this anymore.
