I want to exclude some files from instrumenting. I can't use 'vendors' or 'helpers' because these files should be placed in particular position in code (in my case, after instrumented code)
Just realized that I can include these files under specs so that they load after src but before the real specs....but this is a bit of a hack and won't work in every scenario
closes #14 and #17, new files option and function support for replace
Introduced files option in v0.3.1.