Add wallet version to handshake and emit an event on version upgrade. (already implemented in browser mode. check 'new-version-detected' event)
Print a warning message if the connecting peer has a higher wallet version
Not accepting blocks from peers with lower versioned wallet
Print a warning message each time a lower wallet versioned peer sends a block hash. (eg : "Not fetching block : "XXX" from peer : "AAA" since peer's version is old. expected : "0.2.3" actual: "0.2.1" )
Notifying peers about wallet version changes
Not accepting blocks from peers with lower versioned wallet