[Harbour] Extensions - possible cleanup?

[Szakáts Viktor]

>> The problem is we already use .hbl for compiled language files, so
>> I cannot make above change.
>
> How about .hblib? No requirements that extensions be 3 chars, it's  
> more just a habit.

Not just a habit, Harbour (and of course hbmk2) also supports
DOS, and potentially other such limited OSes/filesystems where
LFN isn't available. So in Harbour core we stick to 8.3 names.

Brgds,
Viktor