Update contributing guide (#794)

* Update contributing guide

Fixes #786

Signed-off-by: Andrew Ferrazzutti <andrewf@element.io>

* Commonize PR template with IRC bridge

Signed-off-by: Andrew Ferrazzutti <andrewf@element.io>

* changelog

Signed-off-by: Andrew Ferrazzutti <andrewf@element.io>

.github/pull_request_template.md

+<!--
+Hi there 👋, please check you've read the [CONTRIBUTING](../CONTRIBUTING.md) guide before submitting a PR (it's worth it, honestly).
+-->

CONTRIBUTING.md

-Hello! It's awesome that you want to contribute to the Discord bridge, by doing
-so you are helping our users and the wider Matrix ecosystem. This document
-lists the requirements for your work to be accepted into our repository.
+Hi there! Please read the [CONTRIBUTING.md](https://github.com/matrix-org/matrix-appservice-bridge/blob/develop/CONTRIBUTING.md) guide for all matrix.org bridge
+projects.
 
-For clarity reasons, work can either be a pull request or an issue. We find
-both quite valuable to the project. Please note that your work must abide by
-the Apache 2 license found in the LICENSE file.
+## matrix-appservice-discord Guidelines
 
-Most importantly we are a welcoming project and will be happy to review any
-works, no matter the skill level of the submitter. Everyone must start
-somewhere!
-
-## TL;DR
-
-* Always work off the **develop** branch. We won't accept merges into any other branches.
-
-* We follow the [Matrix Code of Conduct](https://matrix.org/docs/guides/code_of_conduct.html) and will not accept or entertain works from individuals who break it. We believe in considerate and respectful members above accepting works, regardless of quality.
-  * This includes possible bans from any room(s) involved with the project.
-* We are limited to accepting work over Github. Please use its interface when submitting work items.
 * Discussion of ideas for the bridge and work items should be in [#discord:half-shot.uk](https://matrix.to/#/#discord:half-shot.uk).
 * Everything submitted as a PR should have at least one test, the only exception being non-code items.
 
@@ -36,52 +22,15 @@ inside the `MatrixEventProcessor` class.
 ## Setting up
 
 * You will need to [setup the bridge](https://github.com/Half-Shot/matrix-appservice-discord/tree/develop#setup-the-bridge) similarly to how we describe,
-  but you should setup a homeserver locally on your development machine. We would recommend [Synapse](https://github.com/matrix-org/synapse#id11).
-
-## Writing an issue
-
-When writing an issue, please be as verbose as you can. Remember the issue is
-there to either document a feature request, or report a bug so it can be fixed.
-The issue board is NOT there to complain about a broken or missing feature.
-
-We leave it to the author's discretion to decide what to include rather than
-provide a template, but good items are:
- * Shorter titles are better than long rambling ones, but please don't make it too vague.
-    * A good example is "Ability to bridge an existing matrix room into a discord channel"
- * A brief description of the problem.
-    * If you are a user of another person's bridge, please can you let us know the name of the service provider.
-    * If you would like to keep the details private, please PM @Half-Shot:half-shot.uk or @sorunome:sorunome.de discreetly.
- * Relevant logging from Synapse/your homeserver AND the bridge (if applicable).
-    * The more verbose, the better but please don't include sensitive details like access tokens.
- * A screenshot is always useful.
- * Please mention which direction a failure is in, e.g. Matrix -> Discord, if applicable.
-
-We will assign each issue a tag, which will allow us to categorise the problems.
-
-While we realise some issues are more important than others, please do not "demand"
-for an issue to be fixed. Issues will be worked on in the timeframe that best fits
-the needs of the team.
-
-
-## PR Process
-
-We've tried our best to keep the PR process relatively simple:
-
-* Create a new branch based off the `develop` branch.
-    * This can be done with `git checkout develop` followed by `git checkout -b featurename`.
-* Create a PR on Github, making sure to give a brief discription of your changes and link to the issue it fixes, if any.
-    * If your change is not complete but you would like feedback, create it as a draft.
-* Ensure the linter and tests are not failing, as we will not accept code that breaks either.
-    * If your tests fail and are having trouble fixing them, you may push your changes and we will help you fix them.
-    * Github automatically pokes TravisCI to run both linting and tests.
-* Someone from the team will review your work and decide what to do with the PR.
-    * Usually we will have feedback for the PR and will submit more comments.
-    * We may decide to reject it, if a feature does not fit with the project goals.
+  but you should setup a homeserver locally on your development machine. We would recommend [Synapse](https://github.com/matrix-org/synapse).
 
 ## Testing
 
-Testing the bridge is easy enough, you just need to run `npm run build`,
-`npm run lint` and `npm run test`. If all pass without errors, congratulations!
+CI will lint and test your code automatically,
+but you can save yourself some time by checking locally before submitting code.
+Refer to the main matrix.org bridge contributing guide for instructions on how to
+[lint](https://github.com/matrix-org/matrix-appservice-bridge/blob/develop/CONTRIBUTING.md#%EF%B8%8F-code-style) and
+[test](https://github.com/matrix-org/matrix-appservice-bridge/blob/develop/CONTRIBUTING.md#-tests--ci).
 
 Please bear in mind that you will need to cover the whole, or a reasonable
 degree of your code. You can check to see if you have with `npm run

changelog.d/794.doc

+Update `CONTRIBUTING.md` guide to reference the newly-updated guide for all of the matrix.org bridge repos.