README: Adds Google Group - Mailing List
README: Adds Google Group - Mailing List

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johnmarinelli/nmatrix,johnmarinelli/nmatrix,agisga/nmatrix,wlevine/nmatrix,johnmarinelli/nmatrix,agisga/nmatrix,thisMagpie/nmatrix,agisga/nmatrix,wlevine/nmatrix,thisMagpie/nmatrix,thisMagpie/nmatrix,janusnic/nmatrix,agisga/nmatrix,janusnic/nmatrix,janusnic/nmatrix,wlevine/nmatrix,janusnic/nmatrix,johnmarinelli/nmatrix,thisMagpie/nmatrix,wlevine/nmatrix