Updates
* New features
* Added switch for setting p0 based on prior fits
* Added 1n custom variable output to inspect tab
* Added x limits to fitting
* Added unique id label ('year.run') and made this the default
* Simplified tab names, made tabs larger and easier to click
* Disallowed fit parameters to be both shared and fixed.
* Added the 1e run mode
* Bug fixes
* Specifies TkAgg matplotlib backend to account for differences in raise window command
* Fixed fitstyle error on fitting for more than 8 runs. Omitting legend now works.
* Fetch data tab checkbox labels now update on fetch
* Fixed extra blank matplotlib figures popping up when redraw mode selected and no figure active
* Unselecting runs in fetch tab also removes corresponding plotted result in fit tab
* Export data now properly sets .csv file extension