Install dependencies if missing. Fix #169.

[thw26]

This PR resolves #169. It does so by doing a few things. It creates the functions getOS¹, getPackageManager (which also sets the package dependencies lists), and installPackages (a basic wrapper for our variables). Further, it modifies check_cmds and check_libs to install packages if missing.

It also simplifies the dependency checks and moves them further down the installer's process. This is the only way to keep the script from having to do this twice (i.e., once for base dependencies, once for version specific dependencies). To help with this, it also creates a new logosSetup function. Also, remember that the initial checks of the script are for a dialog program and for whether the system is running a GUI environment.

Finally, it makes the AppImage install the default/recommended method, as we know it works on all system's without having to deal with the wine staging requirement, and the AppImage install is the only option that always appears on the list as is. All this to say, it is our "stable" install.

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TODO

• The package names need to be verified.
• Add package manager yes flags
• Add apk support.
• Add zypper support.
• Add pkg support? See Make Script BSD Compatible #150.
• Update the README
• Update the CHANGELOG
• Update the script version

Footnotes

1. This function is not heavily used at the moment but available just in case. Some distros will change a package name though it uses the same package manager and we may need to utilize this. Right now its only purpose is for installing libfuse3 on Debian-based systems. ↩

[jg00dman]

A fantastic idea!

[thw26]

Closed in favor of #193 due to non-fast-forward.