Rule idea: residualPrint

[nicklockwood]

When using print debugging it's common to accidentally leave print statements in the code afterwards. This rule would remove them.

(Since this is a bit unsafe, it might be better if it operated as lintonly by default, but we don't have that capability yet)

Note: while seemingly trivial, there are some edge cases where removing print would change semantics, e.g. if it causes the implicit return type of a closure to change.