[build] Use latest Orbit release

Author: spoenemann

gradle/p2-deployment.gradle

@@ -19,7 +19,7 @@ p2gen {
 		bundle 'com.google.guava'
 	}
 	dependencies {
-		repositoryUrl 'http://download.eclipse.org/tools/orbit/downloads/drops/S20170516192513/repository'
+		repositoryUrl 'http://download.eclipse.org/tools/orbit/downloads/drops/R20170818183741/repository'
 		bundle {
 			id 'com.google.gson'
 			version versions.gson_orbit

releng/releng-target/lsp4j.target.target

@@ -7,7 +7,7 @@
 			<unit id="com.google.guava" version="0.0.0"/>
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="false" type="InstallableUnit">
-			<repository location="http://download.eclipse.org/tools/orbit/downloads/drops/S20170516192513/repository"/>
+			<repository location="http://download.eclipse.org/tools/orbit/downloads/drops/R20170818183741/repository"/>
 			<unit id="com.google.gson" version="2.7.0.v20170129-0911"/>
 			<unit id="com.google.gson.source" version="2.7.0.v20170129-0911"/>
 		</location>