Updated version to 0.8.0
Libraries are installed in lib directly with symbolic links, not in lib/rtabmap-0.8. Removed the need of RPATH in cmake.
Saving variance of each link in database (new field Link.variance). The variance is used to generate the constraint information matrices for TORO optimization.
ICP: computing variance instead of fitness.
ICP3: added correspondences ratio parameter
Added OdometryInfo class
Refactoring: renamed depth2d stuff to laserScan. rtabmap::Memory and rtabmap::Signature classes (no more distinct neighbor, loop closure or child loop closure links, only links with different types)