Fixes eclipse-jdtls/eclipse.jdt.ls#99

I have added the java.implementationsCodeLens.enabled property, false by default.
To enable the codeLens implementors, you have to add the following:

"java.implementationsCodeLens.enabled": true

The implementations will be shown for interfaces and abstract classes.

Requires eclipse-jdtls/eclipse.jdt.ls#301

Signed-off-by: Snjezana Peco snjezana.peco@redhat.com