Rewrite mktables from scratch.

Rewrite mktables from scratch.
- Cleaner.
- Faster: 15-20 seconds as opposed to several minutes.
- More dynamic: the names of the various categories
  such as the linebreak ones are dynamic, not static.
- Is.pl: long names for the general category properties
  are now available.
- Ranges (<... ,First>, <..., Last>) from the general
  categories work now.
- No more mktables.PL because the mktables.PL is not
  and never has been run to create a mktables.
- syllables.txt and Is/Syl*.pl removed: non-standard
  (not part of the Unicode), and the whole concept is
  being reworked (http://syllabary.sourceforge.net/),
  the old way wouldn't even work with the new Syllables.txt
  (it would result in 1000+ new categories)

p4raw-id: //depot/perl@12427