Fix for uninitialized covariance matrix
Fix for uninitialized covariance matrix

Lead to unpredictable tracking termination criteria.

rgkoo/libmv-blender,SoylentGraham/libmv,rgkoo/libmv-blender,petertsoi/libmv,SoylentGraham/libmv,rgkoo/libmv-blender,petertsoi/libmv,petertsoi/libmv,rgkoo/libmv-blender,SoylentGraham/libmv,SoylentGraham/libmv,rgkoo/libmv-blender,petertsoi/libmv