Fix all pylint errors and add pylint to CI pipeline

Fixes all of the 90 pylint errors: about 2/3rds of these are meaningless lint stuff but I fixed so that pylint can be added to the CI pipeline. 1/3rd of course are real bugs, some of which actually would come up fairly frequently. Adds pylint to CI pipeline: all warnings and anything of severity below that are ignored. Should be good for checking really simple untested stuff like that ``comfy.sd`` issue that came up yesterday - sometimes it takes a hot minute to write a test and the pylint will catch the obvious. The last commit of this repo can be rolled back if we don't want to add it to CI.