Doc: HPSF & Gov Links (#5085)

Add agreed upon HPSF boilerplate text in README and manual.
Update acknowledegments.

Author: ax3l

Docs/source/acknowledgements.rst

@@ -3,13 +3,18 @@
 Funding and Acknowledgements
 ============================
 
-WarpX is supported by the Exascale Computing Project (17-SC-20-SC), a collaborative effort of two U.S. Department of Energy organizations (Office of Science and the National Nuclear Security Administration) responsible for the planning and preparation of a capable exascale ecosystem, including software, applications, hardware, advanced system engineering, and early testbed platforms, in support of the nation's exascale computing imperative.
+WarpX is hosted by the High Performance Computing Foundation (HPSF).
+If your organization wants to help steer the evolution of the HPC software ecosystem, visit `hpsf.io <https://hpsf.io>`__ and consider joining!
 
 WarpX is supported by the CAMPA collaboration, a project of the U.S. Department of Energy, Office of Science, Office of Advanced Scientific Computing Research and Office of High Energy Physics, Scientific Discovery through Advanced Computing (SciDAC) program.
 
-ABLASTR seed development is supported by the Laboratory Directed Research and Development Program of Lawrence Berkeley National Laboratory under U.S. Department of Energy Contract No. DE-AC02-05CH11231.
+WarpX is supported by the KISMET project, a project of the U.S. Department of Energy, Office of Science, Office of Advanced Scientific Computing Research and Office of Fusion Energy Science, Scientific Discovery through Advanced Computing (SciDAC) program.
 
 CEA-LIDYL actively contributes to the co-development of WarpX.
 As part of this initiative, WarpX also receives funding from the French National Research Agency (ANR - Plasm-On-Chip), the Horizon H2020 program and CEA.
 
+WarpX was supported by the Exascale Computing Project (17-SC-20-SC), a collaborative effort of two U.S. Department of Energy organizations (Office of Science and the National Nuclear Security Administration) responsible for the planning and preparation of a capable exascale ecosystem, including software, applications, hardware, advanced system engineering, and early testbed platforms, in support of the nation's exascale computing imperative.
+
+ABLASTR seed development was supported by the Laboratory Directed Research and Development Program of Lawrence Berkeley National Laboratory under U.S. Department of Energy Contract No. DE-AC02-05CH11231.
+
 We acknowledge all the contributors and users of the WarpX community who participate to the code quality with valuable code improvement and important feedback.

README.md

@@ -8,7 +8,7 @@
 [![Discussions](https://img.shields.io/badge/chat-discussions-turquoise.svg)](https://github.com/ECP-WarpX/WarpX/discussions)  
 [![Supported Platforms](https://img.shields.io/badge/platforms-linux%20|%20osx%20|%20win-blue)](https://warpx.readthedocs.io/en/latest/install/users.html)
 [![GitHub commits since last release](https://img.shields.io/github/commits-since/ECP-WarpX/WarpX/latest/development.svg)](https://github.com/ECP-WarpX/WarpX/compare/development)
-[![Exascale Computing Project](https://img.shields.io/badge/supported%20by-ECP-orange)](https://www.exascaleproject.org/research/)
+[![HPSF](https://img.shields.io/badge/hosted%20by-HPSF-orange)](https://hpsf.io)
 [![Language: C++17](https://img.shields.io/badge/language-C%2B%2B17-orange.svg)](https://isocpp.org/)
 [![Language: Python](https://img.shields.io/badge/language-Python-orange.svg)](https://python.org/)  
 [![License WarpX](https://img.shields.io/badge/license-BSD--3--Clause--LBNL-blue.svg)](https://spdx.org/licenses/BSD-3-Clause-LBNL.html)
@@ -45,6 +45,14 @@ To contact the developers, feel free to open an issue on this repo, or visit our
 [![SENSEI](https://img.shields.io/static/v1?label="runs%20on"&message="SENSEI"&color="blueviolet")](https://sensei-insitu.org)
 
 Our workflow is described in [CONTRIBUTING.rst](CONTRIBUTING.rst).
+We invite you to contribute to WarpX in any form following our [Code of Conduct](https://warpx.readthedocs.io/en/latest/coc.html), e.g., contribute to [discussions](https://github.com/ECP-WarpX/WarpX/discussions), help each other in [issues](https://github.com/ECP-WarpX/WarpX/issues), fix bugs, or add [documentation](https://warpx.readthedocs.io/en/latest/developers/documentation.html) and new functionality!
+
+## Governance
+
+WarpX is hosted by the High Performance Computing Foundation (HPSF).
+If your organization wants to help steer the evolution of the HPC software ecosystem, visit [hpsf.io](https://hpsf.io) and consider joining!
+
+The WarpX open governance model is described in [GOVERNANCE.rst](GOVERNANCE.rst).
 
 ## Copyright Notice