The target 'atarixl' is to be used for Atari XL (and better) machines.
It will disable the OS ROM and enable the Shadow RAM available on
those machine.
Note: This commit is only the inital step towards for this goal that just
replicates the target 'atari' as a starting point!
1. Implements a real progress bar.
2. Decomposes the timer's result.
git-svn-id: svn://svn.cc65.org/cc65/trunk@4496 b7a2c559-68d2-44c3-8de9-860c34a00d81