expand the description and clean up some of the english in the docs
expand the description and clean up some of the english in the docs

cookpad/chanko,taiki45/chanko,damoguyan8844/chanko,cookpad/chanko,damoguyan8844/chanko,taiki45/chanko,r7kamura/chanko,r7kamura/chanko,cookpad/chanko,taiki45/chanko,damoguyan8844/chanko