Adding L2 transfer tools glossary (#424)

* Adding L2

* from Ethereum

Author: MichaelMacaulay

website/pages/en/glossary.mdx

@@ -79,3 +79,5 @@ title: Glossary
 - **Graph CLI**: A command line interface tool for building and deploying to The Graph.
 
 - **Cooldown Period**: The time remaining until an Indexer who changed their delegation parameters can do so again.
+
+- **L2 Transfer Tools**: Smart contracts and UI that enable network participants to transfer from Ethereum mainnet to Arbitrum One. Network participants can transfer delegated GRT, subgraphs, curation shares, and Indexer's self stake.