Reportseff

To simplify site wide installations, dropped the minimum python version to 3.6.2 and click to 6.7

Modified how sacct errors were caught to provide better error messages when a user is passed that doesn't exist.
Modified the since option. Now when used without specifying user, will add --allusers to sacct unless jobs or directories are explicitly added.

By integrating with the jobstats caching at Princeton University HPC systems, reportseff is able to pull out more accurate node usage statistics and GPU usage. Reports can include values split by GPUs or nodes.

If jobs have other AdminComment contents, an exception will be raised. Please report these so I can modify the parsing routine to be more flexible.

Fixed a typo which caused long output to be directed to console instead of through a pager.

Fixed import error with python 3.7 caused by a missing dependency (and some pinning issues).

What's Changed
* more helpful Output_Renderer.validate_title() error msg by janosh in https://github.com/troycomi/reportseff/pull/4
* replaced several parsers with regex to improve correctness and flexibility
* implemented hypermodern python tooling
* can truncate front of columns

New Contributors
* janosh made their first contribution in https://github.com/troycomi/reportseff/pull/4

**Full Changelog**: https://github.com/troycomi/reportseff/commits/v1.0.0