Add a CONTRIBUTING guide

Also adds a brief installation guide to the README

Author: Beau Shinkle

CONTRIBUTING.adoc

@@ -0,0 +1,57 @@
+= Keep Contribution Guide
+
+🎉 Thanks for taking the time to contribute! 🎉 Contributions are welcome from
+anyone, and even the smallest of fixes is appreciated!
+
+The following is a set of guidelines for contributing to Keep and its packages.
+These are mostly guidelines, not rules. Use your best judgment, and feel free to
+propose changes to this document in a pull request.
+
+== Getting started
+
+1. Fork https://github.com/keep-network/tbtc-v2[`keep-network/tbtc-v2`]
+2. Clone your fork
+3. Follow the
+   link:README.adoc#Installation[installation & build steps] in the README.
+4. Set up the <<Development Tooling>>.
+5. Open a PR against the `main` branch and describe the change you are intending
+   to undertake in the PR description.
+
+Before marking the PR as ready for review, make sure:
+
+* It passes the linter checks (see <<Pre-commit>> to make this automatic).
+* It passes the https://github.com/keep-network/tbtc-v2/actions[continuous
+  integration tests].
+* Your changes have sufficient test coverage (e.g regression tests have
+  been added for bug fixes, unit tests for new features)
+
+== Development Tooling
+
+Commits
+https://help.github.com/en/articles/about-commit-signature-verification[must
+be signed].
+
+=== Continuous Integration
+
+Keep uses https://github.com/keep-network/tbtc-v2/actions[Github Actions] for
+continuous integration. All jobs must be green to merge a PR.
+
+=== Pre-commit
+
+Pre-commit is a tool to install hooks that check code before commits are made.
+It can be helpful to install this, to automatically run linter checks and avoid
+pushing code that will not be accepted. Follow the
+https://pre-commit.com/[installation instructions here], and then run
+`pre-commit install` to install the hooks.
+
+=== Linting
+
+Linters and formatters for Solidity, JavaScript, and Go code are set up and run
+automatically as part of pre-commit hooks. These are checked again in CI builds
+to ensure they have been run and are passing.
+
+If you want to change a rule, or add a custom rule, to the JavaScript or
+Solidity linting, please propose these changes to our
+https://github.com/keep-network/solium-config-keep[solium-config-keep] and
+https://github.com/keep-network/eslint-config-keep[eslint-config-keep] packages.
+All other packages have it as a dependency.

README.adoc

@@ -59,3 +59,41 @@ wallet accepts new deposits, and the oldest wallet serves redemptions.
 Depositing Bitcoin into the tBTCv2 bridge grants a transferable Bank balance, which
 can be used to mint a supply-pegged ERC-20: TBTC. For an in-depth explanation
 about the design, see link:docs/rfc/rfc-1.adoc[RFC 1: tBTCv2 Design].
+
+== Installation
+
+=== Prerequisites
++ clone the repository
++ link:https://nodejs.org/en/[Node.js] v14.21.2
++ yarn: `$ npm install -g yarn`
++ configure git to use https
+
+```
+git config --global url."https://".insteadOf git://
+```
+
++ python v3.X. Must have a `python` binary pointing to version 3.X, not just an
+alias (for `node-gyp`). On osx, this did the trick:
+```
+brew install python
+sudo ln -s /opt/homebrew/bin/python3 /opt/homebrew/bin/python
+```
+
+=== Install and Test Contracts
+
+```
+cd solidity
+yarn install
+yarn build
+yarn test
+yarn test:integration
+```
+
+=== Install and Test TypeScript Library
+
+```
+cd typescript
+yarn install
+yarn build
+yarn test
+```