Add `cptrash` and `mvtrash` scripts

[Thyrum]

A common way for me to delete files is by overwriting them with newer versions. Replacing all ways of overwriting files might be a bit overkill (because there are many ways to do so, think of ln for example) but adding alternatives for the most common ways of overwriting files would be helpfull.

If no one else takes this on, I will probably do this myself when I have time.

[jakob1379]

This could easily be achieved with an alias and would probably just seem like bloat in the available options, IMO.