change CvMat#get_rows, CvMat#get_cols
change utility functions' name

REGISTER_CVMETHOD -> REGISTER_HASH
LOOKUP_CVMETHOD -> LOOKUP_HASH
replace rb_hash_aref to rb_hash_lookup (or LOOKUP_HASH)
move pyr_segmentation to IplImage
update CvMat#moments
update tests of CvMat#corner_harris
update tests of CvMat#inpaint
update tests of CvMat#optical_flow_*
update tests of CvMat#match_template
update tests of CvMat#pre_corner_detect
update tests of CvMat#pyr_up
update tests of CvMat#pyr_mean_shift_filtering
update tests of CvMat#log_polar