* Unvectorize xstrlcpy

On all libcs I could find, memcpy does a better job than we can.

* Rename xstrlcpy to xstrsncpy to avoid confusion

The semantics of our xstrlcpy differed slightly from strlcpy; we return
the number of copied characters; strlcpy returns the strlen(src).
strscpy from Linux is similar except it returns the number of copied
characters sans the NUL byte, so this is named strsncpy to be different.

See https://no-color.org

* Added fzfz plugin

* Fixed shellcheck errors

* Fixed copy/paste error

* Added support for fzy, also renamed plugin since it's not specific to fzf anymore

* Refactored code

* Clean spillovers (jarun)

* Added fzfz plugin

* Fixed shellcheck errors

* Fixed copy/paste error

Install with `make install-desktop`
It now appears in application menus, search, etc. in XDG compatible
desktop environments (like GNOME, KDE, ...).