started working on a script which generates images from text files

the text files must end with ".pixx" and be located in the same
directory as generate.py (which has to be called from that directory)

the files must contain a matrix of 7 rows and 5 columns, a '#' indicates
a burning LED and a space (or anything else, really) everything else.
deleted test file for generating image strings
excluded *.pixx files from version control
included one test file nonetheless