fix links (#158)

README.md

@@ -4,7 +4,7 @@
 
 [Optimism](https://optimism.io/) is a Public Benefit Corporation dedicated to scaling Ethereum in a way that enshrines fair access to public goods. Optimism is focused on implementing a production-level Optimistic Rollup implementation that integrates with the Optimistic Virtual Machine (OVM) to scale arbitrary Solidity smart contracts.
 
-To get involved, follow us on [Twitter](https://twitter.com/optimismPBC), join our [Discord](https://discordapp.com/invite/jrnFEvq), and try out our [OVM tutorial](https://github.com/ethereum-optimism/ERC20-Example)!
+To get involved, follow us on [Twitter](https://twitter.com/optimismPBC), join our [Discord](https://discord.gg/cf4AErQ), and try out our [OVM tutorial](https://github.com/ethereum-optimism/ERC20-Example)!
 
 `@optimism-monorepo` is the Optimism monorepo.
 All of the core Optimism projects are hosted inside of the [packages](https://github.com/ethereum-optimism/optimism-monorepo/tree/master/packages) folder of this repository.

packages/docs/developer-documentation/getting-started/README.md

@@ -1,6 +1,6 @@
 # Getting Started
 
-If you're looking to integrate with the OVM, welcome! You've come to the right place. Please note that the OVM is still in Alpha, and integrating now will inevitably uncover bugs. If you do, feel free to reach out to our [discord](https://discord.gg/cveQWV) or create a Github issue. We love talking to early adopters--don't be a stranger!
+If you're looking to integrate with the OVM, welcome! You've come to the right place. Please note that the OVM is still in Alpha, and integrating now will inevitably uncover bugs. If you do, feel free to reach out to our [discord](https://discord.gg/cf4AErQ) or create a Github issue. We love talking to early adopters--don't be a stranger!
 
 To get you up to speed, you can follow along with our ERC20 conversion tutorial which takes a simple ERC20 EVM contract, and shows you how to transpile and run tests through the OVM. After that you will find some general notes on the current status of the OVM and helpful debugging tips.
 

packages/test-ERC20-Waffle/README.md

@@ -96,4 +96,4 @@ The OVM provides a fresh new take on layer 2 development: it's identical to laye
 ## Troubleshooting
 Not working for you? It might help to check out this [easy to read Diff](https://i.imgur.com/DEU7wXC.png) to show you exactly which lines you should be altering. You can also check out the final working codebase that we have added to a seperate branch [here](https://github.com/ethereum-optimism/ERC20-Example/tree/final_result)
 
-Still not working? [Create a Github Issue](https://github.com/ethereum-optimism/ERC20-Example/issues), or hop in our [Discord](https://discordapp.com/invite/jrnFEvq) channel and ask away.
+Still not working? [Create a Github Issue](https://github.com/ethereum-optimism/ERC20-Example/issues), or hop in our [Discord](https://discord.gg/cf4AErQ) channel and ask away.