Feature request: slugify

[Ginden]

Three problems:

• certain programs break when confronted with file names containing non-ASCII (this is especially visible for Windows - eg. username Michał will lead you in trouble, because some files will end in C:\Users\Micha\ and others will end in C:\Users\Michał\)

• certain programs break when confronted with file names containing colons (it breaks Windows on OS level and causes trouble for rsync) or spaces (these are just poorly written).

My suggestion is to provide way to normalize file names - using algorithm similar to eg. slug.

[qarmin]

Normalizing names I implemented in #47

This is only an option and users may do whatever they want with files(if they want to have colons or spaces in names I won't stop them since this is not my data).

I'm using slugmin my fork of slug-rs library which allows to use _, (space ) and ., since I think this characters are useful(anyone can use replace rule to remove them).