Formatting.
Replacing many enums with #defines since we do arithmetics (especially
ORing which would produce undefined enum values). The ideal thing instead
of #defines is `const int' as provided in C++...
Adding header files to rules.mk
- removed a stupid memory leak
- fixed the weird metrics hinting (the horizontal edges were used,
instead of the vertical one, to compute the metrics adjustments,
silly, silly, silly).
there is still some bugs that I'm looking at though, but we're
very near the release..