Add tests for opencv_3d

[WanliZhong]

All tests are based on the googletest framework.

RAC_FIT_PLANE:

Test the basic function ransacFitPlanes(...) of RANSAC detect planes algorithm.

1. SinglePlaneDetectionAccuray: Test whether a single plane can be correctly identified.
2. SinglePlaneDetectionWithNormAccuray: Test whether a single plane can be correctly identified with normal vector.
3. MultiPlaneDetectionAccuray: Test whether multiple planes can be correctly identified.
4. SinglePlaneDetectionWithNormAccuray: Test whether multiple planes can be correctly identified with normal vector.

SAMPLING:

Test the basic functions voxelGrid(...), randomSampling(...) and farthestPointSampling(...) of RANSAC detect planes algorithm.

1. VoxelGridFilterSampling: Test whether the cube with side length of 1 will be simplified to a point when the grid size is 1.1.
2. RandomSampling: Test whether a point can be selected randomly from the cube.
3. FarthestPointSampling: Test whether the two sampling points are the farthest point pair.

TLS:

Test the basic functions totalLeastSquaresPlaneEstimate(...) of RANSAC detect planes algorithm.

1. ThreePointsPlane: Test the plane coefficient formed by three normal points.
2. ThreePointsLine: Test the plane coefficient formed by 3 points on a line.
3. LinePerpendiularAxis: Test the plane coefficient formed by 3 points on a line perpendicular to the coordinate axis.
4. PlaneInAxis: Test the plane coefficient formed by 3 points in the coordinate axis plane.