Improvements and new APIs

• feat: allow defining memory block options via limiterManager.use method 3d80aa3
• refactor: prefix throttle middleware ip key with ip_ 6b6398c
• refactor: allow connectionName in redis config to be optional 155eed4
• feat: add decrement method use atomic upserts for increment method ee886a3

Full Changelog: v2.1.2...v2.2.0