readme updates (#149)

* Update README.md

fix discord link.

* update cli readme and contributing guide

README.md

@@ -7,6 +7,7 @@
 
 <a href="https://discord.gg/vBPpJkS"><img src="https://img.shields.io/badge/chat-discord-brightgreen.svg?logo=discord&style=flat"></a>
 <a href="https://twitter.com/intent/follow?screen_name=HasuraHQ"><img src="https://img.shields.io/badge/Follow-HasuraHQ-blue.svg?style=flat&logo=twitter"></a>
+<a href="http://eepurl.com/dzefQj"><img src="https://img.shields.io/badge/newsletter-subscribe-yellow.svg?style=flat"></a>
 
 Hasura GraphQL Engine is a blazing-fast GraphQL server that gives you **instant GraphQL APIs over Postgres**. Hasura helps you build GraphQL apps backed by Postgres or incrementally move to GraphQL for existing applications using Postgres.
 
@@ -74,7 +75,7 @@ Hasura works with any GraphQL client. We recommend using [Apollo Client](https:/
 
 The documentation and community will help you troubleshoot most issues. However, if you have encountered a bug or need to get in touch with us, you can contact us using one of the following channels:
 
-* Support & feedaback: [Discord](https://discord.gg/vBPpJkS)
+* Support & feedback: [Discord](https://discord.gg/3FNQnWj)
 * Issue & bug tracking: [Github issues](https://github.com/hasura/graphql-engine/issues)
 * Follow product updates: [@HasuraHQ](https://twitter.com/hasurahq)
 * Talk to us on our [website chat](https://hasura.io)

cli/CONTRIBUTING.md

@@ -22,7 +22,7 @@ follow the instructions below to make sure the import paths are correct:
 - `make deps`
 - Work on the feature/fix
 - If you modify files in `assets/`, run `make assets`
-- Add tests and ensure all tests are passing (`make test`)
+- Add tests and ensure all tests are passing (check [Tests](#tests) section below)
 - Commit, push and submit PR
 
 ## Development workflow
@@ -50,7 +50,7 @@ When you're adding a new feature, it is encouraged to add integration tests (uni
 The tests expect a GraphQL Engine server instance to be running. You can point the tests to any GraphQL Engine server but please note that **the database should be empty**. The easiest way to do this is to run an Postgres and GraphQL Engine using [Docker Compose](https://github.com/hasura/graphql-engine-install-manifests). Once the server is running, you can run the tests by executing the make command:
 
 ```bash
-HASURA_GRAPHQL_TEST_ENDPOINT=http://localhost:8080 make test
+HASURA_GRAPHQL_TEST_ENDPOINT=http://localhost:8080 VERSION=dev make test
 ```
 
 ## Builds
@@ -62,4 +62,4 @@ To build a binary, execute the following command:
 make build
 ```
 
-This will output cross-platform binaries to `_output` directory.
+This will output cross-platform binaries to `_output` directory.

cli/README.md

@@ -2,7 +2,7 @@
 
 ## Installation
 
-Download GraphQL Engine CLI bundled with Hasura CLI
+### Download GraphQL Engine CLI bundled with Hasura CLI
 
 - Linux/macOS
 ```bash
@@ -11,11 +11,22 @@ curl -L https://cli.hasura.io/install.sh | bash
 - Windows: [installer](https://cli.hasura.io/install/windows-amd64)
 
 
-or download using go get
+### Download using go get
+
 ```bash
 go get github.com/hasura/graphql-engine/cli/cmd/hasura
 ```
 
+### Build from source
+
+```bash
+git clone https://github.com/hasura/graphql-engine
+cd graphql-engine/cli
+make deps
+make build
+# binaries will be in _output directory
+```
+
 ## Usage
 
 ```bash