Fix wrong JDK version in README.md.
Fix wrong JDK version in README.md.

deltaspike/parent/pom.xml states <java.version>1.8</java.version>.

Signed-off-by: Juri Berlanda <5bfdca9e82c53adb0603ce7083f4ba4f2da5cacf@hotmail.com>

struberg/deltaspike,apache/deltaspike,apache/deltaspike,struberg/deltaspike,struberg/deltaspike,struberg/deltaspike,apache/deltaspike,apache/deltaspike