Changes

Update m2e-maven-runtime build deps.
* Tycho 1.2.0 to 1.4.0
* Maven bundle 2.5.4 to 3.5.0
* Compiler plugin 3.7.0 to 3.8.1
* Fix warnings reported by maven
Change-Id: I403a401ca2e2653a6716d16ff876cba1ee6795c3 Signed-off-by:
Alexander Kurtakov <akurtako@redhat.com>