This ensures the compiler compiles against the public, supported and
documented API for a specific VM version (here 11) [1]. This also means
that
we don't need EE descriptors in Eclipse anymore in order to ensure that
only supported APIs of the selected Java version can be used.
According to [2] if option --release is used --source and --target
options can't be used.
While we are at it also add default value for all new jdt core options
added in Eclipse 4.21.
[1] https://docs.oracle.com/en/java/javase/11/tools/javac.html
[2] https://docs.oracle.com/en/java/javase/14/docs/specs/man/javac.html#option-release
Change-Id: I852a5d7b0a3210751c15d79ec91915b4c01c41e2
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>