Feature indexZeroPrefixed

[clouless]

I would love to have an index prefixed with zeros.
Here is my first draft of the feature with unit Tests to discuss further.

Readme Additions

[75lb]

hi, thanks for the input - nice patch! However, it's a very specific use case - something more suited to an external plugin.. Please use this feature on your own fork temporarily while I upgrade renamer to accept plugins as input.

[clouless]

ok no problem :) Then we close this PR and maybe you can ping me once renamer supports plugins :)

[75lb]

In version v1 of renamer, you can specify a printf format with --index-format. So, to get the 0001, 0002 etc numbering scheme:

$ renamer -r "Image{{index}}" --index-format "%04d" --dry-run *

Install the prerelease:

$ npm install -g renamer@next