refactor the class Seeds in region growing module
refactor region growing module -- basic version
modify neighbor module: the input parameter REF is removed  from init function to compute function
refactor region growing module -- version 2
add in2d and intersect2d to do set operator in 2D array
refactor SeededRegionGrowing Class. Now, It can work.
Merge pull request #4 from zhenzonglei/rg

refactor SeededRegionGrowing Class. Now, It can work.