started work on simple gui

in development. not using the header_lines callback or anything related to
the listbox right now. going to have to figure out how to update that to
get thie file list from the directory.
resolved a bit of mess from earlier cherry-picking
number of headerlines works

at least, it works as far as i can tell right now.
listbox populates with filenames

also added length declaration back into drop.m constructor. i messed up
deleting that whole line when i was removing the class-level datatype.
fixed name of tester in readme
Merge branch 'master' into gui

Conflicts:
	drop.m
deleted subprocess that don't work
Merge branch 'master' into gui

Conflicts:
	drop.m
fixed path issues
*not working* -- continued work on gui
load_data:things are in the right spot, don't work
all the uielements work
fixed verbosity
Merge branch 'master' into gui
fixed gui for new lib path
started process_data
Merge branch 'master' into gui
Merge branch 'master' into gui
renamed processes & added back test
Merge branch 'master' into gui