Fri 16 Sep 2022 : in the test functions showVersion.jl, showPolynomial.jl,
  showSystem.jl, showDimension.jl, showMixedVolume.jl, showSolve.jl, and
  showStableMixedVolume.jl, replace the old module name JuPHC by PHCpack.

Tue 13 Sep 2022 : renamed JuPHC.jl into PHCpack.jl.

Tue 15 Mar 2022 :  mixedVolume.jl, showMixedVolume.jl, stableMixedVolume.jl,
  showStableMixedVolume.jl are added, updated JuPHC.jl.
