since yaml.load() is deprecated, and the loaded stuff does not need
to be complex anyways, use yaml.safe_load(). This gets rid of the
deprecated yaml.load() method and uses the safe approach for loading
yaml files
You can now place a file name '.courseignore' in the ROOT directory
and specify - in each line - the name of a directory. Directories named
this way and located in the ROOT directory will not be treated as course
directories
