Started testing PDDL problem parsing for a Blocks World problem.

tests/data/blocksworld-problem.pddl

@@ -0,0 +1,7 @@
+(define (problem BLOCKS-4-0)
+(:domain BLOCKS)
+(:objects D B A C - block)
+(:INIT (CLEAR C) (CLEAR A) (CLEAR B) (CLEAR D) (ONTABLE C) (ONTABLE A)
+ (ONTABLE B) (ONTABLE D) (HANDEMPTY))
+(:goal (AND (ON D C) (ON C B) (ON B A)))
+)