Small coding - big improvements :)

[Daniel Le Berre <leberre@xxxxxxxxxxxxxxxxxxx>]

Dear all,

I added yesterday a few lines of code to SAT4J to mimic Rsat decision 
heuristics (i.e. previous assignments are kept while 
restarting/backtracking in order to avoid repeating the mistakes twice).

I ran the new solver (MiniLearningHeapRsatExpLearning) on the SAT Race 
conditions and the new solver solved 58 benchmarks versus 52 using the 
default SAT solver MiniLearningHeapExpLearning.

If some of you could try that new solver on their benchmarks, I would be 
happy to have their opinion about it.

Cheers,

   Daniel