incease compatibility of autonum

[janhajer]

the etextools package loaded by autonum conflicts with biblatex.
However only a single command from etextools is used in autonum.
Therefore I propose to remove the dependency and provide the command within autonum.

Furthermore, autonum is compatible with cleveref.
However not with all its commands. I have added compatibility with Cref and labelcref.

The test containing Umlaute fails however, as far as I know this is not supposed to work within Latex.
Therefore I have commented out these test.

[mstarodub]

Thanks so much for the fix @janhajer - it works great for me.
Have you considered forking the package and uploading it to ctan? That would be much appreciated. I think at this point it's fair to assume that the original maintainer isn't active anymore.

[MagicMuscleMan]

Sorry, I indeed have not find the time and motivation to work on it and this is unlikely to change. Please get in touch with me if you want to be added to the github project.