Added debug messages to http req/res method, improved debug output

Change-Id: Id00a89ed93f7b7c6e9dbd4914ab656ae7895e1cf
diff --git a/src/com/mirantis/mk/Common.groovy b/src/com/mirantis/mk/Common.groovy
index d4b817c..1c958b5 100644
--- a/src/com/mirantis/mk/Common.groovy
+++ b/src/com/mirantis/mk/Common.groovy
@@ -144,13 +144,8 @@
  * @param color Colorful output or not
  */
 def debugMsg(msg, color = true){
-    def debugEnabled
-    try {
-        debugEnabled = DEBUG
-    } catch (MissingPropertyException e) {
-        debugEnabled = false
-    }
-    if(debugEnabled){
+    // if debug property exists on env, debug is enabled
+    if(env.getEnvironment().containsKey('DEBUG')){
         printMsg("[DEBUG] ${msg}", "red")
     }
 }