PathSpring stretch output declared in constructProperties(), but should be declared in constructOutputs().
Basic prototype of a tree iterator.
Preliminary work on filtering out a specific Component subclass.

I get a segfault right now when trying to filter out only Foo's. Not sure what
the cause is. The tree and iterator are now more intimately tied to
Component's.
Use namestr() instead of name() for Output's.
Changed Force to Actuation for all relevant Actuator's member functions
(to make naming more consistent and descriptive; including fcns as getForce, setForce,
computeOverrideForce, overrideForce, isForceOverriden, setOverrideForce, getOverrideForce)
Merge latest master to ForceToActuationRename branch
Added more explanation to getStress comments.
Adjusted some spacing
Renamed variable force to actuation in TorqueActuator::computeForce
(to clarify actuation is being overridden not force)
Removed comments left to check QueryPerformanceCounter
(as it's not used anymore and we just use e.g. std::clock_t startTime = std::clock();)
Renamed output actuation to use lowercase
(to be compatible with conventions)
Removed doxygen-style comments in Actuator.cpp and kept only internal comments.
Updated ScalarActuator comments to reflect the Rename
Updated actuation signals to actuation.
Another, simpler iterator that works by traversing the tree in PreOrder fashion as a linked list.
Fix compilation errors on gcc and clang due to last commit.
Use postfix increment operator for iterator in test
changed some API references to get/set Force()
replaced setForce with setActuation
changed back to getForce