Improved Documentation

[RhysPeploe]

https://github.com/openjournals/joss-reviews/issues/6322

The addition of:

• [x] a README.md file and / or a description in 'About'
• [x] directions on how to install the package in the paper and the GitHub. The paper referrences to https://cran.r-project.org/web/packages/gsMAMS/index.html but for the sake of less experienced R users, it would be good to include the install.packages() and library() commands to improve remove neccassary barriers to using the package
• [x] Community guidelines for third parties wishing to 1) Contribute to the software 2) Report issues or problems with the software 3) Seek support

would improve the package.

[Tpatni719]

Thank you so much for the suggestions! I have added the recommendations in the package.