Changes

IPFS (Interplanetary File System) is used by Ravencoin for issuance meta-data, messaging, and transaction meta-data. Ravencoin must interact with IPFS in order to show messages because the message content is stored on IPFS. IPFS access should be on by default, but should be able to be turned off with a flag. A two phase approach will allow Ravencoin to use IPFS natively, but it will also use existing IPFS proxies.