readme: update the api of 'CMatrixBlock()'
src: support to get a block from the block itself
src: fix a mistake about English sentence.
src: add some files for linting pass
src: add instance methods 'row()' and 'col()'
test: add instance methods 'row()' and 'col()' testings

fix some mistakes
update instance method block()’ testings
src: update some api about block
readme: add instance methods 'row()' and 'col()' api
Merge branch 'feature/instance_method_row_and_col' into develop