Changed default log output to std::cout
Added iSAM2 support and done basic debuggings
Fixed small bugs and added support for pruning candidates
Fixed small bugs and added support for pruning candidates
Added some debugging options
Fixed a bug in FinishCycle
Added support for LoopDetector
Added support for iSAM2Interface
	new file:   apps/test_isam.py
	modified:   apps/test_octomap.py
	modified:   common/SLAMInterface.cpp
	modified:   common/SLAMInterface.h