Allow coexistance of each packege

[rikutons]

Resolves #49.

First package's symlink will be preserved because removing other package's file is not permitted.

Idk whether I need to change from

provides=('xremap')

to

provides=('xremap', 'xremap-wlroots')

. So please consider it.

[njkevlani]

@k0kubun, is it necessary to install xremap as /usr/bin/xremap? If we can install it with different names, like /usr/bin/xremap-x11-bin, /usr/bin/xremap-wlroots-bin, etc. If we can, then we can remove this step:

    if [ ! -L /usr/bin/xremap ]; then
      ln -sfT xremap-gnome "${pkgdir}/usr/bin/xremap"
    fi

This step makes the installation a bit unpredictable.

[k0kubun]

I want to call the command name xremap throughout the documentation. So I want xremap to be usable just like before this PR.

I'm open to whatever way both @rikutons and @njkevlani are happy with. If you don't like the if [ ! -L /usr/bin/xremap ]; then behavior, please suggest an alternative. I'm not open to dropping the xremap command name, so I would rather not change anything if we were to implement @njkevlani's idea.

Plus, I want to eventually make a single binary support all variants because all of the current binaries don't require extra dependencies (thanks to x11rb being a pure-Rust binding). We will not have this problem once it's solved, so let's keep making xremap available, at least by default.

[rikutons]

Sure, I think I should better be waiting until better solution created if in the future it will be solved by it. As @njkevlani said it will be unpredictable so not best for default impl, I'll agree it. It's not kind as a default-behavior.

Now I can use my patch to solve it and gladly wait one-binary feature. Plz close it if there is no alternative way, @njkevlani .

[njkevlani]

Let’s wait for the single binary solution :)

Closing the PR for now.