message: Add new CMake to the Dockefile
diff: @@ -14,12 +14,16 @@ ARG LLVM_VERSION=10.0
  RUN uname -a
  # Packages required to build ISPC and Clang.
  -RUN apt-get -y update && apt-get install -y build-essential gcc g++ git python3 ncurses-dev libtinfo-dev cmake && \
  +RUN apt-get -y update && apt-get install -y wget build-essential gcc g++ git python3 ncurses-dev libtinfo-dev && \
  rm -rf /var/lib/apt/lists/*
  # If you are behind a proxy, you need to configure git and svn.
  #RUN git config --global --add http.proxy http://proxy.yourcompany.com:888
  +# Download and install required version of cmake (3.13) for ISPC build
  +RUN wget https://github.com/Kitware/CMake/releases/download/v3.13.5/cmake-3.13.5-Linux-x86_64.sh && mkdir /opt/cmake && sh cmake-3.13.5-Linux-x86_64.sh --prefix=/opt/cmake --skip-license && \
  + ln -s /opt/cmake/bin/cmake /usr/local/bin/cmake && rm cmake-3.13.5-Linux-x86_64.sh
  +
  WORKDIR /usr/local/src
  # Fork ispc on github and clone *your* fork.
  