Add config objects for asyncRetrySimple & asyncRetryCustom

What's Changed

• Update eslint dependency by @Marketionist in #44
• Add config objects for asyncRetry by @Marketionist in #45
• Add tests for asyncRetry by @Marketionist in #46
• Update logLevel checks by @Marketionist in #47
• Update notifications & errors by @Marketionist in #48
• Update asyncRetry usage examples by @Marketionist in #49

Full Changelog: v1.7.0...v1.8.0