Add partial (or fuzzy) search for the module name in the mix task spirit.gen

[waseem-medhat]

As a QoL improvement: if a wrong name is provided as an arg to mix spirit.gen, instead of printing the entire list of module names, we could only print those that might be close matches to the given arg.

A simple partial (substring) match is the easiest to add. But maybe we can get fancy with a string distance metric or something similar.