Merge pull request #330 from domaframework/support-java13

Clarify support for Java 13

Author: nakamura-to

README.md

@@ -77,6 +77,7 @@ Major versions
 | Java 10 |        |   v    |
 | Java 11 |        |   v    |
 | Java 12 |        |   v    |
+| Java 13 |        |   v    |
 
 License
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