q1-still needs checking
Merge remote-tracking branch 'origin/master' into graph_plan
q5
q6 incomplete
q6
q8
q1-q8

Plan found with 6 actions in 2.03 seconds
q9

dwr1 :Plan found with 10 actions in 45.05 seconds
is this too long? smtng wrong or just exp growth?
Remove unnecessary checks
Made contains_pairwise_mutex static
Merge pull request #16 from Jirsch/graph_plan

Graph plan- /1-9