Added an settings option for AssertThatCollectionOrMap inspection respecting the degenerated case of maps with null values.
Upgrade to JUnit Jupiter 5.5.2.
Unrelated: Upgraded Gradle to 5.4.1. Upgraded kotlin to 1.3.40. Upgraded jacoco to 0.8.4. Minor style change for immediate returns. Increased test/branch coverage.
Fixed an exception in batch mode if the description string was the same but for different fixes. Now descriptions are different for quick fixes triggered by AssertThatJava8OptionalInspection and AssertThatGuavaOptionalInspection. Minor refactorings. Extended documentation.