isPositiveNumber / isNegativeNumber

• chore: build 22e44ea
• feat: add isPositiveNumber / isNegativeNumber 35623b9
• feat(docs): greatly improve docs 05d4ae4
• chore: update dependencies 2a0da4a
• build: rename "typings" → "types" 088429c

v4.0.0...v4.1.0