add CForest planning framework

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branch : CForest
doc fixes, clean-up, use persistent scratch space for pruning to avoid mallocs

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branch : CForest
show helpful msg if no progress plot can be generated
The way projection settings were stored in params could cause crashes. Fixed now. CForestStateSpaceWrapper copies missing state space properties from spaces it wraps. General CForest clean-up.

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branch : CForest
extra : close : 1
Merge
fix for static initialization issues in random seed generator
fix for static initialization issues in state space allocation
order planner solutions by cost if an optimization objective is used, otherwise order by path length