* need to fix one test case shouldGraduallyIncreaseLimitWhenHealthy failing for AdaptiveRateLimiter.java
* Added Class Diagram and Flow Diagrams for Adaptive, Fixed Window and Token Bucket Rate Limiter
* Updated README.md. All test case passed. Updated with Google Java Guidelines
* Updated parent pom #2973
* Updated parent pom #2973
* fixed shouldResetCounterAfterWindow() test #2973
* formatting fixed#2973
* added test coverage for app.java and fixed random to be thread safe #2973
* added test coverage for app.java and fixed random to be thread safe #2973
* added test coverage for app.java and fixed random to be thread safe #2973
* added test coverage for app.java and fixed random to be thread safe #2973
* added test coverage for app.java and fixed random to be thread safe #2973
* added test coverage for app.java and fixed random to be thread safe #2973
* added test coverage for app.java and fixed random to be thread safe #2973
* fixed random to be thread safe #2973
* fixed random to be thread safe #2973
* fixed random to be thread safe #2973
* fixed spacing in pom.xml #2973
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Co-authored-by: Ilkka Seppälä <iluwatar@users.noreply.github.com>
