Update to jdtls version 0.39

Author: appelgriebsch

lib/main.js

@@ -11,8 +11,8 @@ const {
   removeUnusedImportProvider
 } = actionProviders
 
-const serverDownloadUrl = 'http://download.eclipse.org/jdtls/milestones/0.38.0/jdt-language-server-0.38.0-201905021936.tar.gz'
-const serverDownloadSize = 39046507
+const serverDownloadUrl = 'http://download.eclipse.org/jdtls/milestones/0.39.0/jdt-language-server-0.39.0-201905150127.tar.gz'
+const serverDownloadSize = 39070941
 const serverLauncher = '/plugins/org.eclipse.equinox.launcher_1.5.300.v20190213-1655.jar'
 const minJavaRuntime = 1.8
 const bytesToMegabytes = 1024 * 1024