Prepare for API change in JDT

With support for Java 8, bundle org.eclipse.jdt.core 3.10.0 introduces a new method IMethod.isLambdaMethod
We'll soon move to a newer target-platform based on Luna M7 that will include this bundle, so affected projects need to prepare a PR that:

• tighten version range for JDT (set 3.10 as minimum)
• implement this method in the local class.

You can use the following Target-Platform suggested in https://github.com/jbosstools/jbosstools-target-platforms/pull/60 to get access to this bundle.

CC xcoulon@redhat.com & snjeza_jira