[maven-release-plugin] prepare release jcommander-1.21
[maven-release-plugin] prepare release jcommander-1.21

madrob/jcommander,selliera/jcommander,cbeust/jcommander,selliera/jcommander,cbeust/jcommander,winndows/jcommander,selliera/jcommander,madrob/jcommander,cbeust/jcommander,TKlerx/jcommander,VikingDen/jcommander