Merge branch 'release/0.0.51' into develop
src: add instance method 'minCoeff()'
test: add instance method 'minCoeff()' testings
readme: instance method 'minCoeff()' api

fix a mistake
lint: add some files for linting pass
npm: 0.0.51 -> 0.0.52
Merge branch 'release/0.0.52'