Fix for embark build --contracts writing into the pipeline

Author: emizzle

lib/index.js

@@ -194,7 +194,9 @@ class Embark {
         engine.startService("libraryManager");
         engine.startService("codeRunner");
         engine.startService("web3");
-        engine.startService("pipeline");
+        if(!options.onlyCompile){
+          engine.startService("pipeline");
+        }
         engine.startService("deployment", {onlyCompile: options.onlyCompile});
         engine.startService("storage");
         engine.startService("codeGenerator");
@@ -209,6 +211,9 @@ class Embark {
         engine.logger.info("Finished deploying".underline);
         // Necessary log for simple projects. This event is trigger to soon because there is no file
         // Also, not exiting straight after the deploy leaves time for async afterDeploys to finish
+        if(options.onlyCompile){
+          return callback();
+        }
         engine.logger.info("If you have no files to build, you can exit now with CTRL+C");
         engine.events.on('outputDone', callback);
       }