Merge #246

246: post-JOSS cleanup r=odunbar a=odunbar

<!--- THESE LINES ARE COMMENTED -->
## Purpose 
<!--- One sentence to describe the purpose of this PR, refer to any linked issues:
#14 -- this will link to issue 14
Closes #2 -- this will automatically close issue 2 on PR merge
-->
Clean-up after JOSS paper

## Content
<!---  specific tasks that are currently complete 
- Solution implemented
-->
- put paper md,bib and pdf in `JOSS/`, 
- add "citing us" to readme, 
- remove paper generation on git push

<!---
Review checklist

I have:
- followed the codebase contribution guide: https://clima.github.io/ClimateMachine.jl/latest/Contributing/
- followed the style guide: https://clima.github.io/ClimateMachine.jl/latest/DevDocs/CodeStyle/
- followed the documentation policy: https://github.com/CliMA/policies/wiki/Documentation-Policy
- checked that this PR does not duplicate an open PR.

In the Content, I have included 
- relevant unit tests, and integration tests, 
- appropriate docstrings on all functions, structs, and modules, and included relevant documentation.

-->

----
- [x] I have read and checked the items on the review checklist.


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

README.md

@@ -2,6 +2,11 @@
 Implements optimization and approximate uncertainty quantification algorithms, Ensemble Kalman Inversion, and Ensemble Kalman Processes.
 
 
+## Citing us
+
+If you use the examples or code, please cite our article at JOSS in your published materials.
+
+
 | **Documentation**    | [![dev][docs-latest-img]][docs-latest-url]       |
 |----------------------|--------------------------------------------------|
 | **DOI**              | [![DOI][zenodo-img]][zenodo-latest-url]          |
@@ -34,3 +39,4 @@ Implements optimization and approximate uncertainty quantification algorithms, E
 
 ### Requirements
 Julia version 1.6+ 
+