Removed duplicate doc files

[uppittu11]

PR Summary:

Fixes #269

PR Checklist

---

• Includes appropriate unit test(s)
• Appropriate docstring(s) are added/updated
• Code is (approximately) PEP8 compliant
• Issue(s) raised/addressed?

[codecov]

Codecov Report

Merging #270 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #270   +/-   ##
=======================================
  Coverage   85.75%   85.75%           
=======================================
  Files          10       10           
  Lines        1137     1137           
=======================================
  Hits          975      975           
  Misses        162      162

[mattwthompson]

Just to check, it looks like forcefields.rst isn't a part of the current docs site?

https://mosdef.org/foyer/index.html

Although there's a mismatch in the filename (https://mosdef.org/foyer/forcefields.html) and title (Parameter definitions) which seems to be a part of the confusion

[uppittu11]

It looks like the website was looking in forcefield.rst for the Parameter Definitions page. I believe this is fixed with the update to index.rst, but I have not rebuilt the website and verified this yet.

[ahy3nz]

Yeah looks like the docs need forcefields.rst to make the "parameter definitions page" while parameter_definitions.rst doesn't make that page. I'm just selectively removing these rst files, make clean, make dirhtml and looking at the resultant documentation pages, but I'm curious why parameter_definitions.rst doesn't get compiled into the docs

[mattwthompson]

Approving because Parashara was able to build this locally 👍