MSX version update

While writing a version for another platform (the Grundy NewBrain), I noticed that there was an issue with the timer routine for the MSX version. It turns out that the code was in there for the MSX version was using the MSX clock, however, it was not calculating the time properly, The MSX has a fine-grained timer which allows me to measure the time to the nearest 0.1 second as required for the z-machine standard. This makes the MSX version one of the few that I have written which supports the full fine-grained time requirement.

While for normal text adventures, this timer resolution might not make much difference, some of the fun post-Infocom games, this distinction is used. One of the games that I've tested which works properly now is the `bomber.z5`, a real time game where you need to drop bombs from the plane to create a flat landing for your plane. Check the screenshot below for the action!

There's also an update for CP/M 2.2 versions to fix the issue where a blank file name is entered or aborted for a game save. The updated code will be included in all future version updates, even though not all versions were impacted.