support more characters in strings
create support for checking partial configurations again
fix issue with select of unknown item
failin test case for integer default dependencies
refine mechanism to write to .dimacs files

experimented with BDDs, but some formulas are simply to big

for example BITREVERSE is selected by several features
with rather complex constraints producing constraints
with 72 variables that would require over a billion
CNF clauses

keeping simple mechanism to write from SAT formulas with extra variables
facilities to write nonboolean values in header
facilities to write completedconf.h (very slow)
fix parser
support for defaults depending on other defaults
support for named choices (requires undertaker patch)