Added proper errorlevels

releng/dobuild.sh

@@ -14,7 +14,14 @@ printf "Updating templates..."
 printf "Running prebuild..."
 cd build
 mono bin/Prebuild.exe /target nant
-
+if [ $? -eq 0 ]
+  if [ $? -eq 0 ]
     printf "Doing the build..."
     nant
+  else
+    exit 1
+  fi
+else
+  exit 1
+fi