Add support pathauto with tokens

The patch on #7 is working for me with Subgroup 3.0. Thank you!

Hi

After needed a token for subgroups as well and doing my own version , i have just found the patch (cause i did not think about it before)
Patch seems to work fine in subgroup 3.x :D :D
Tomorrow will do a bit more tests.

Thnks

I just wrote a similar implementation and wanted to submit that here, but then found this issue and compared the solutions. They are almost identical. So, I tested this one and it works like a charm. Setting to RTBC and would be happy if it could be merged.

The patch doesn't properly apply any longer, so I'm creating an MR for the 3.1 branch.