replaced --output option definition + replaced with ,

public/biopet-extentsions/src/main/scala/nl/lumc/sasc/biopet/extensions/sambamba/SambambaView.scala

@@ -43,6 +43,6 @@ class SambambaView(val root: Configurable) extends Sambamba {
     optional("--format", format.get) +
     optional("--regions", regions) +
     optional("--compression-level", compression_level) +
-    required("--output" + output) +
+    required("--output", output) +
     required(input)
 }