No need to document 'copy' option

[jonathantneal]

No need to test for copy either, because it doesn’t exist. The default option is replace, but any other option becomes copy before, effectively.

[MattDiMu]

Thx for reviewing and yes, you're right. The implementation isn't smooth, as any passed method results a copy before behavior. I should change this to a more defensive approach, where invalid options result in the default replace behavior.

Btw, do you see any valid use case for a copy after method?