Update README.md and Dockerfile for Ubuntu 23.10, GCC GFortran 13.2.0, and dependency package updates. (#1)

* Update README.md

Updated README.md to describe the updates to Ubuntu 23.10.

* Update Dockerfile for Ubuntu 23.10

Modified the Dockerfile to use Ubuntu 23.10 so we can pick up new Linux Kernel enhancements and the GCC GFortran v13.2.0 compiler. Also updated the package installation processes to account for revisions to package names and how they need to be installed.

* Formatting

---------

Co-authored-by: milancurcic <[email protected]>

Author: jnorrid

Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:18.04
+FROM ubuntu:23.10
 
 ENV USERNAME=backus
 
@@ -8,13 +8,14 @@ RUN apt-get -yq update && apt-get -yq install sudo
 # create and switch to a user
 RUN echo "backus ALL=(ALL) NOPASSWD:ALL" >> /etc/sudoers
 RUN useradd --no-log-init --home-dir /home/$USERNAME --create-home --shell /bin/bash $USERNAME
-RUN adduser $USERNAME sudo
+RUN usermod -aG sudo $USERNAME
+#RUN adduser $USERNAME sudo
 USER $USERNAME
 WORKDIR /home/$USERNAME
 
 # install packages
 RUN sudo apt-get install -yq git curl && \
-    sudo apt-get install --no-install-recommends -yq make cmake gfortran libcoarrays-dev libopenmpi-dev open-coarrays-bin && \
+    sudo apt-get install --no-install-recommends -yq make cmake gfortran libcoarrays-dev libopenmpi-dev libcoarrays-openmpi-dev libcaf-openmpi-3&& \
     sudo apt-get clean -q
 
 # get modern-fortran code

README.md

@@ -1,10 +1,13 @@
 # modern-fortran-docker
 
 Dockerfile to build a modern-fortran Docker image.
-It's based off Ubuntu 18.04 and installs gfortran, OpenMPI, and OpenCoarrays for you.
+It's based off Ubuntu 23.10, which has several enhancements to the Linux kernel and supports 
+GCC GFortran v13.2.0.
+
+This Dockerfile installs gfortran, OpenMPI, and OpenCoarrays for you.
 It will also git clone the modern-fortran projects.
 
-You will need Docker set up and running on your system.
+You will need Docker to be set up and running on your system.
 
 ## Build
 
@@ -28,4 +31,5 @@ docker run -it modern-fortran:latest /bin/bash
 
 ## Thanks
 
-Maurizio Tomassi who provided the original Dockerfile.
+* Maurizio Tomassi who provided the original Dockerfile
+* Joshua Norrid who updated the Dockerfile for use with Ubuntu 23.10