FUEL: improved highlighting of alien syntax; TYPEDEF, C-TYPE, STRUCT and UNION-STRUCT
FUEL: better matching for hex numbers, eg. 0xDeadBeefBabe
FUEL: Improved highlighting of stack effect declarations for alien functions. Types are highlighted bold using the new face factor-font-lock-type-in-stack-effect.
FUEL: improve handling of whitespace in regexps
FUEL: highlight alien callbacks identical to functions
FUEL: fix regexp for number literals