Spack install instructions for Building section. (#2602)

Adds instructions for how to install AMReX using Spack to the Building with AMReX section.

Author: etpalmer63

Docs/sphinx_documentation/source/BuildingAMReX.rst

@@ -743,3 +743,38 @@ This capability is not supported on Windows.
 (3) Memory profiling is an optional feature in AMReX that is not enabled by default.  It reads
 memory system information from the OS to give us a summary of our memory usage.  This is not
 supported on Windows.
+
+
+.. _sec:build:spack:
+
+Spack
+=====
+
+AMReX can be installed using the scientific software package manager Spack. Spack
+supports multiple versions and configurations of AMReX across a wide variety of platforms
+and environments. To learn more about Spack visit http://www.spack.io. For system requirements and
+installation instructions please see https://spack.readthedocs.io/.
+
+Once Spack has been downloaded and the Spack environment enabled, AMReX can be
+installed with the command,
+
+.. code-block:: bash
+
+   spack install amrex
+
+This will install the latest release of AMReX and required dependencies if needed.
+
+AMReX can be built in several combinations of versions and configurations. Available options can
+be viewed by typing,
+
+.. code-block:: bash
+
+   spack info amrex
+
+For example, suppose we want to install the development version of AMReX for a two dimensional
+simulation with Cuda support for Cuda Architecture ``sm_60``. Then we would
+use the install commands,
+
+.. code-block:: bash
+
+   spack install amrex@develop dimensions=2 +cuda cuda_arch=60

Docs/sphinx_documentation/source/BuildingAMReX_Chapter.rst

@@ -3,8 +3,9 @@
 Building AMReX
 ===================
 
-In this chapter, we discuss AMReX's build systems.  Additionally, it
-is also possible to install AMReX using spack (https://spack.io/).
+In this chapter, we discuss AMReX's build systems. Additionally, it
+is also possible to install AMReX using Spack (https://spack.io/).
+For more information see the :ref:`sec:build:spack` section.
 
 There are three ways to use AMReX's build systems. Most AMReX
 developers use GNU Make. With this approach, there is no installation

Docs/sphinx_documentation/source/GettingStarted.rst

@@ -12,8 +12,9 @@ on a monthly basis with version number YY.MM (e.g., 17.04). The MM part of the
 version is incremented every month, and the YY part every year.  Bug fix
 releases are tagged with YY.MM.patch (e.g., 17.04.1).
 
-AMReX can also be obtained using spack (https://spack.io/).  Assuming
-you have spack installed, simply type "spack install amrex".
+AMReX can also be obtained using Spack (https://spack.io/).  Assuming
+you have Spack installed, simply type, ``spack install amrex``. For more
+information see the :ref:`sec:build:spack` section in Building AMReX.
 
 Example: Hello World
 ====================