New 2nd Layer category (Rollups) and added Cartesi Project

README.md

@@ -55,6 +55,7 @@ Many thanks to the ~100 contributors including [@corbpage](https://twitter.com/c
       - [Scalability](#scalability)
       - [Payment/State Channels](#paymentstate-channels)
       - [Plasma](#plasma)
+      - [Rollups](#rollups)
       - [Side-Chains](#side-chains)
       - [Privacy / Confidentiality](#privacy--confidentiality)
         - [ZK-SNARKs](#zk-snarks)
@@ -502,6 +503,9 @@ Many thanks to the ~100 contributors including [@corbpage](https://twitter.com/c
 * [Plasma Guard](https://github.com/mesg-foundation/plasma-guard) - Automatically watch and challenge or exit from Omisego Plasma Network when needed.
 * [Plasma OmiseGo Watcher](https://github.com/mesg-foundation/service-plasma-omisego-watcher) - Interact with Plasma OmiseGo network and notifies for any byzantine events.
 
+#### Rollups
+* [Cartesi](https://docs.cartesi.io/cartesi-rollups/) - Cartesi is an app-specific rollup protocol with a virtual machine that runs Linux distributions, creating a richer and broader design space for DApp developers. Cartesi Rollups offer a modular scaling solution, deployable as L2, L3, or sovereign rollups, while maintaining strong base layer security guarantees.
+
 #### Side-Chains
 * [POA Network](https://www.poa.network/)
   * [POA Bridge](https://bridge.poa.net/)