Clean up PADDING_TODO.txt
PADDING_TODO.txt contains various tasks that should be done. We should figure out which ones should be done before 0.4.0 gets released and which ones are good-to-have features/fixes for later.
PADDING_TODO.txt contains various tasks that should be done. We should figure out which ones should be done before 0.4.0 gets released and which ones are good-to-have features/fixes for later.