Merge branch 'development' into feature/portal-ledger-support

* development: (437 commits)
  Publish
  Update yarn.lock
  Update the CHANGELOG
  Fix the bug making it impossible to specify the custom ZRX address
  Fix fill/cancel order by looking for NoError instead of empty blockchainErr given the BlockchainErrs type refactor
  Add a comment about a yarn bug
  Add our mainnet and kovan nodes as backups for Portal requests
  Fix bug hiding the user info from topBar
  Add dev-utils package to top level README
  Prettier newline
  Prettier
  Allow Token symbols to be alphanumeric
  Update CHANGELOG, rebase on development
  Should not -> cannot
  Reject negative amounts in isValidBaseUnitAmount
  Re-add changelog for 0x.js
  Fix prettier
  Update yarn.lock
  Move tests to a separate folder
  Change file layout
  ...

# Conflicts:
#	packages/website/README.md

1 files changed, 77 insertions, 10 deletions

diff --git a/packages/subproviders/README.md b/packages/subproviders/README.md
index 5fa31611a..d7b80f7ee 100644
--- a/packages/subproviders/README.md
+++ b/packages/subproviders/README.md
@@ -1,15 +1,32 @@
-Subproviders
------------
+## @0xproject/subproviders
 
-A few useful subproviders.
+A few useful web3 subproviders including a LedgerSubprovider useful for adding Ledger Nano S support.
 
 ## Installation
 
 ```
-npm install @0xproject/subproviders --save
+yarn add @0xproject/subproviders
 ```
 
-## Subproviders
+## Usage
+
+Simply import the subprovider you are interested in using:
+
+```javascript
+import {
+    ledgerEthereumBrowserClientFactoryAsync as ledgerEthereumClientFactoryAsync,
+    LedgerSubprovider,
+} from '@0xproject/subproviders';
+
+const ledgerSubprovider = new LedgerSubprovider(
+    networkId,
+    ledgerEthereumClientFactoryAsync,
+);
+
+const accounts = await ledgerSubprovider.getAccountsAsync();
+```
+
+### Subproviders
 
 #### Ledger Nano S subprovider
 
@@ -23,17 +40,67 @@ A subprovider which attempts to send an RPC call to a list of RPC endpoints sequ
 
 A subprovider that relays all signing related requests to a particular provider (in our case the provider injected onto the web page), while sending all other requests to a different provider (perhaps your own backing Ethereum node or Infura).
 
-### Integration tests
+## 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.
+
+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
+```
+
+```bash
+yarn install
+```
+
+### Build
+
+```bash
+yarn build
+```
+
+### Clean
+
+```bash
+yarn clean
+```
+
+### Lint
+
+```bash
+yarn lint
+```
+
+### Run tests
+
+#### Unit tests
+
+```bash
+yarn run test:unit
+```
+
+#### Integration tests
 
 In order to run the integration tests, make sure you have a Ledger Nano S available.
 
-- Plug it into your computer
-- Unlock the device
-- Open the on-device Ethereum app
-- Make sure "browser support" is disabled
+* Plug it into your computer
+* Unlock the device
+* Open the on-device Ethereum app
+* Make sure "browser support" is disabled
 
 Then run:
 
 ```
 yarn test:integration
 ```
+
+#### All tests
+
+```bash
+yarn run test:all
+```