Show progress in terminal title

[mhier]

It would be nice to see the progress while building the packages to have a rough idea how long the build will take. This could be done by setting the terminal title before starting a package build like this:

[/] Building

Alternatively one could set a static line at the top or bottom of the terminal window with appropriate escape sequences to contain that information. In that case one should also use proper exit handlers to reset the scroll window even if the scripts aborts in error or the user hits Ctrl+C.