satsyn - Prune rules to check earlier
satsyn - Prune rules to check earlier

1. Keep track of eligible transition rules down the recursion line.
   Right now, the eligible rules (may_rules) are classified by "not
   making the solution invalid" - which means they don't add any
   livelocks if used in combination with the current set of rules.
   I threw in some TODOs for 2 more constraints.
  c. satsyn.c  synsearch()

grencez/protocon,grencez/protocon,grencez/protocon,grencez/protocon