Implicit targets with template extensions default to copy

[jayvdb]

foo.jj2: foo.jj2 could default to copy.

For coala , and the other times I have implemented moban, this and binary files are only time that the copy: section was necessary.

[chfw]

This looks like a rule that if target file extension is the same as source, it is copy unless template engine is explicitly expressed.

[jayvdb]

yup, that sounds good.