Update contributing notes (plotly#2290)

* update

* updated contributing notes

* code pr in template

* pinning orca

* add doc requirement

Author: emmanuelle

Diff for: .github/pull_request_template.md

@@ -1,5 +1,10 @@
 <!--
-Please uncomment this block and take a look at this checklist if your PR is making substantial changes to documentation/impacts files in the `doc` directory. Check all that apply to your PR, and leave the rest unchecked to discuss with your reviewer! Not all boxes must be checked for every PR :)
+Please uncomment this block and take a look at this checklist if your PR is making substantial changes to **documentation**/impacts files in the `doc` directory. Check all that apply to your PR, and leave the rest unchecked to discuss with your reviewer! Not all boxes must be checked for every PR :)
+
+If your PR modifies code of the `plotly` package, we have a different checklist
+below :-).
+
+### Documentation PR
 
 - [ ] I've [seen the `doc/README.md` file](https://github.com/plotly/plotly.py/blob/master/doc/README.md)
 - [ ] This change runs in the current version of Plotly on PyPI and targets the `doc-prod` branch OR it targets the `master` branch
@@ -20,4 +25,12 @@ Please uncomment this block and take a look at this checklist if your PR is maki
 - [ ] `plotly.plot()` and `plotly.iplot()` are not used in any new/modified example
 - [ ] Hex codes for colors are not used in any new/modified example in favour of [these nice ones](https://github.com/plotly/plotly.py/issues/2192)
 
+## Code PR
+
+- [ ] I have read through the [contributing notes](https://github.com/plotly/plotly.py/blob/master/contributing.md) and understand the structure of the package. In particular, if my PR modifies code of `plotly.graph_objects`, my modifications concern the `codegen` files and not generated files.
+- [ ] I have added tests (if submitting a new feature or correcting a bug) or
+  modified existing tests.
+- [ ] For a new feature, I have added documentation examples in an existing or
+  new tutorial notebook (please see the doc checklist as well).
+
 -->

Diff for: README.md

@@ -8,6 +8,14 @@
             <img src="https://badge.fury.io/py/plotly.svg"/>
         </td>
     </tr>
+    <tr>
+        <td>User forum</td>
+        <td>
+            <a href="https://community.plot.ly"/>
+            <img src="https://img.shields.io/badge/help_forum-discourse-blue.svg"/>
+        </td>
+    </tr>
+
     <tr>
         <td>PyPI Downloads</td>
         <td>
@@ -45,7 +53,7 @@ Read about what's new in [plotly.py v4](https://medium.com/plotly/plotly-py-4-0-
 
 ## Overview
 
-[plotly.py](https://plot.ly/d3-js-for-python-and-pandas-charts/) is an interactive, open-source, and browser-based graphing library for Python :sparkles:
+[plotly.py](https://plot.ly/python) is an interactive, open-source, and browser-based graphing library for Python :sparkles:
 
 Built on top of [plotly.js](https://github.com/plotly/plotly.js), `plotly.py` is a high-level, declarative charting library. plotly.js ships with over 30 chart types, including scientific charts, 3D graphs, statistical charts, SVG maps, financial charts, and more.
 
@@ -61,12 +69,12 @@ Built on top of [plotly.js](https://github.com/plotly/plotly.js), `plotly.py` is
 ---
 
 - [Online Documentation](https://plot.ly/python)
-- [Contributing](contributing.md)
+- [Contributing to plotly](contributing.md)
 - [Changelog](CHANGELOG.md)
 - [Code of Conduct](CODE_OF_CONDUCT.md)
 - [Version 4 Migration Guide](https://plot.ly/python/next/v4-migration/)
 - [New! Announcing Dash 1.0](https://medium.com/plotly/welcoming-dash-1-0-0-f3af4b84bae)
-- [Community](https://community.plot.ly/c/api/python)
+- [Community forum](https://community.plot.ly/c/api/python)
 
 ---