regenerate font cache only when needed
really halt and print message on validation errors
small tweaks

* more open endings on a, e
* larger a
* shift t
* align horizontally i and l
* tweak again W
* make long s look less weird
* make 8 symmetrical
* restore g to full-height
make accents more legible
look better in Eclipse and Specimen.pdf

* slightly shift some letters
* make curly braces symmetrical
* detach ring from a with ring