Introduce hashOnly option that skips writing the file and only outputs map of replacements

[rasmusvhansen]

In a project I am working on, we want to use query parameter based cache busting, and for that purpose we do not need any files to be written. I have introduced a -h parameter that can be used as

hashmark -l 8 -h 'file.js?{hash}'

[keithamus]

Thanks @rasmusvhansen this looks cool! Do you mind also adding a test for this usecase?

[rasmusvhansen]

I will try. The tests don't seem to work on Windows, however as they use Unix specific commands. I will see if I can get it to run on a virtual machine.

[edwinveldhuizen]

It would cool that if in combination with replaceinfiles we could instead of
foo.js -> foo-{hash}.js -> replaced in files to foo-{hash}.js
do something like:
foo.js -> replaced in files to foo.js?{hash}