minor interpreter changes: added command ":bdd" to print current winning
bdd in dot graph notation
method to test bdd sizes
profiling tweaks, logfiles containing computed solutions and bdd
operation statistics
profiling of bdd operations
bdd profiling paths and reordering
bdd profiling bridge condition
improved path calculation: building the transitive closure of
reachability iteratively with Floyd-Warshall-algorithm instead of
computing it recursively
fixed iterative transitive closure and turned off automatic debugging
Merge branch 'performance'