Refine repository links and descriptions in README (#65)

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#### Type of change

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- Documentation update

#### Description
Updated README.md to clarify repository descriptions and add links. Add
link to RFC repo.

---------

Signed-off-by: Yoav Tock <tock@il.ibm.com>

Author: tock-ibm

README.md

@@ -98,10 +98,10 @@ To set up the network yourself, follow the tutorial in the [sample deployment sc
 - [Fabric-X whitepaper](https://eprint.iacr.org/2023/1717.pdf) - detailed description of the Fabric-X. Explains motivation,implementation details and presents performance benchmarks
 - [Fabric-X Committer](https://github.com/hyperledger/fabric-x-committer) Github repository
 - [Fabric-X Orderer](https://github.com/hyperledger/fabric-x-orderer) Github repository
-- [Fabric-X Endorser](https://github.com/hyperledger/fabric-x-endorser)
 - [Fabric-Token-SDK](https://github.com/hyperledger-labs/fabric-token-sdk) and [Fabric-Smart-Client](https://github.com/hyperledger-labs/fabric-smart-client) Github repositories
-- [Fabrix-X Common](https://github.com/hyperledger/fabric-x-common) Github repository - contains new CLIs and protobufs
+- [Fabrix-X Common](https://github.com/hyperledger/fabric-x-common) Github repository - contains new CLIs and protobuf, and code shared between the orderer and committer
 - [Sample deployment scripts](https://github.com/LF-Decentralized-Trust-labs/fabric-x-ansible-collection)
+- [Fabric-X RFCs](https://github.com/hyperledger/fabric-x-rfcs) Github repository - contains request for changes (RFCs) in the Fabric-X project
 
 ## Coming soon...