add singularity description file for Ubuntu 20.04 LTS

BootStrap: docker

From: ubuntu:20.04

%post

    export DEBIAN_FRONTEND=noninteractive

    apt-get update

    apt-get upgrade --no-install-recommends -y

    apt-get install --no-install-recommends -y \

        bc \

        build-essential \

        ccache \

        clang \

        cmake \

        cmake-curses-gui \

        curl \

        doxygen \

        enchant \

        g++ \

        gcc \

        gfortran \

        git \

        hdf5-tools \

        libblas-dev \

        libeigen3-dev \

        libenchant-dev \

        libfftw3-dev \

        libgsl-dev \

        libhdf5-serial-dev \

        libjpeg-dev \

        liblapack-dev \

        libopenblas-dev \

        libpng-dev \

        libproj-dev \

        libvtk6-dev \

        make \

        mpi-default-bin \

        mpi-default-dev \

        ninja-build \

        python3-dev \

        python3-pip \

        python3-pkg-resources \

        python3-setuptools \

        python3-virtualenv \

        rsync \

        ssh \

        texlive \

        texlive-latex-recommended \

        texlive-latex-extra \

        texlive-pictures \

        texlive-publishers \

        texlive-science \

        dvipng \

        vim-nox \

        virtualenv \

        voro++-dev \

        wget \

        xxd

%environment

        LC_ALL=C

        export LC_ALL

%labels

    Author akohlmey, rbberger