Support for non-archinstall systems

[gponcon]

Architect specifies in the readme that Arch need to be installed with "archinstall", but it is also possible to use it with an installation without archinstall (or with specific archinstall settings). Specify what is required for this to work (or integrate an automatic installation of these components):

• Need sudoer user
• Need a functional graphical environment
• Need a basic installation of the desired shell
• etc.