improve(grunt): avoid some tasks to be runned when not needed
improve(grunt): avoid some tasks to be runned when not needed

camunda/camunda-bpm-platform,ingorichtsmeier/camunda-bpm-platform,camunda/camunda-bpm-platform,camunda/camunda-bpm-platform,langfr/camunda-bpm-platform,langfr/camunda-bpm-platform,ingorichtsmeier/camunda-bpm-platform,langfr/camunda-bpm-platform,ingorichtsmeier/camunda-bpm-platform,ingorichtsmeier/camunda-bpm-platform,langfr/camunda-bpm-platform,langfr/camunda-bpm-platform,ingorichtsmeier/camunda-bpm-platform,langfr/camunda-bpm-platform,camunda/camunda-bpm-platform,ingorichtsmeier/camunda-bpm-platform,camunda/camunda-bpm-platform,camunda/camunda-bpm-platform