simplify configuration dependency.
<!-- The normal dependencies with all solvers included. -->
<conf name="runtime"
- extends="runtime-mathsat,runtime-optimathsat,runtime-smtinterpol,runtime-princess,runtime-z3,runtime-cvc4,runtime-boolector,runtime-yices2"
+ extends="runtime-without-gpl,runtime-yices2"
description="all solvers included"/>
<!-- The normal dependencies with all solvers included, except those unter GPL. -->
