Hodo time walk calib (#462)

* Initial commit of time-walk calibration script

* Updates for safe keeping

* Monior tweaks

* Minor edits

* Add time walk function

* Minor tweaks to histo macro, first hack at fit macro

* Add functions for readability

* Added more functionality

* Still hacking out min/max algo

* More tweaks

* Modify cuts for more recent (12/5/17) cosmic running

* Add time walk scripts for HMS

* Update fit ranges and histogram ranges