#123 2 letter space keys should be allowed

[hontvari]

Space keys must be at least 3 letters long now. Please remove this restriction.
Justification: We have not only one but two projects which have a two letters long name. One of the names was an acronym originally, but the scope of the project changed and the old full name would be very deceptive now. I added a '1' to the project name, but this is ugly.
I have seen the same naming pattern in another bug report, so it seems I am not alone with this problem.