Merge branch 'development' into features/orderwatcher_ws

* development: (107 commits)
  Fix OrderWatcher title to fix sidebar top
  Fix version picker so it doesn't overflow onto two lines
  Fix bug in pull_missing_blocks with incorrect start block (#1438)
  Pull approval events for ZRX and DAI (#1430)
  fix semicolon and apply prettier
  Fix dex order quote/base asset assigning (#1432)
  Apply prettier
  Publish
  Updated CHANGELOGS
  Rename contracts CHANGELOGs to DEPLOYs
  Move Forwarder CHANGELOG entries to extensions CHANGELOG
  Make contracts packages not private
  Publish
  Updated CHANGELOGS
  Show @ price in light grey
  Updated CHANGELOGS
  typeof -> isString
  add special case to scrape OHLCV for eth/usd (#1428)
  run linter
  simplify scaling input logic
  ...

1 files changed, 74 insertions, 0 deletions

diff --git a/contracts/tokens/README.md b/contracts/tokens/README.md
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+## Token contracts
+
+Token smart contracts that are used in the 0x protocol. Addresses of the deployed contracts can be found in the 0x [wiki](https://0xproject.com/wiki#Deployed-Addresses) or the [CHANGELOG](./CHANGELOG.json) of this package.
+
+## Usage
+
+Token contracts that make up and interact with version 2.0.0 of the protocol can be found in the [contracts](./contracts) directory. The contents of this directory are broken down into the following subdirectories:
+
+*   [tokens](./contracts/tokens)
+    *   This directory contains implementations of different tokens and token standards, including [wETH](https://weth.io/), ZRX, [ERC20](https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20.md), and [ERC721](https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md).
+*   [test](./contracts/test)
+    *   This directory contains mocks and other contracts that are used solely for testing contracts within the other directories.
+
+## Bug bounty
+
+A bug bounty for the 2.0.0 contracts is ongoing! Instructions can be found [here](https://0xproject.com/wiki#Bug-Bounty).
+
+## Contributing
+
+We strongly recommend that the community help us make improvements and determine the future direction of the protocol. To report bugs within this package, please create an issue in this repository.
+
+For proposals regarding the 0x protocol's smart contract architecture, message format, or additional functionality, go to the [0x Improvement Proposals (ZEIPs)](https://github.com/0xProject/ZEIPs) repository and follow the contribution guidelines provided therein.
+
+Please read our [contribution guidelines](../../CONTRIBUTING.md) before getting started.
+
+### Install Dependencies
+
+If you don't have yarn workspaces enabled (Yarn < v1.0) - enable them:
+
+```bash
+yarn config set workspaces-experimental true
+```
+
+Then install dependencies
+
+```bash
+yarn install
+```
+
+### Build
+
+To build this package and all other monorepo packages that it depends on, run the following from the monorepo root directory:
+
+```bash
+PKG=@0x/contracts-tokens yarn build
+```
+
+Or continuously rebuild on change:
+
+```bash
+PKG=@0x/contracts-tokens yarn watch
+```
+
+### Clean
+
+```bash
+yarn clean
+```
+
+### Lint
+
+```bash
+yarn lint
+```
+
+### Run Tests
+
+```bash
+yarn test
+```
+
+#### Testing options
+
+Contracts testing options like coverage, profiling, revert traces or backing node choosing - are described [here](../TESTING.md).