Revamp support for building third-party apps via maven

- Publish onos-dependencies (autogenerated from deps.json). With most
  3rd-party dependencies listed as <dependencyManagement> to avoid
  version conflicts, and a minimal set listed as <dependencies> to
  simplify child poms. Similarly, we provide a number of plugins already
  configured as <pluginManagement> to support the whole life-cycle of
  apps (from build, to reporting and release).
- Update Maven plugins to work with JDK 11 (checkstyle, pmd, etc.)
- Publish onos-build-conf (with common checkstyle and pmd confs)
- Removed unused checkstyle code
- Fix OSGi version mismatch in deps.json to consistently depend on
  release 6 (the one supported by Karaf 4)
- Update/simplify archetypes to use onos-dependencies as the parent pom

Change-Id: Ic09b34e13fb49eb3d96df623b53a3617bbf7b7e4
diff --git a/tools/build/jdk/BUILD b/tools/build/jdk/BUILD
index 59934fc..0055031 100644
--- a/tools/build/jdk/BUILD
+++ b/tools/build/jdk/BUILD
@@ -3,12 +3,13 @@
 # :default_jdk are expected to be passed as arguments when invoking bazel build
 # (see onos/.bazelrc)
 
+load("//tools/build/bazel:variables.bzl", "DEFAULT_JAVA_VERSION")
 load("@bazel_tools//tools/jdk:default_java_toolchain.bzl", "default_java_toolchain")
 
 default_java_toolchain(
     name = "default_toolchain",
-    source_version = "11",
-    target_version = "11",
+    source_version = DEFAULT_JAVA_VERSION,
+    target_version = DEFAULT_JAVA_VERSION,
     visibility = ["//visibility:public"],
 )