PIP-7: Checking Timestamp Difference in Handshaking

[Ja7ad]

PIP-7: Checking Timestamp Difference in Handshaking

[b00f]

@kehiy

Based on this proposal, if the |now() - hello_message.my_time| > 20, the hello_message is rejected. By rejecting the hello_message, two nodes cannot communicate anymore.
20 seconds is the time of 2 blocks, in the worse case scenario, one of the node may start querying about one missed blocks.
They sync module can tolerate one block, not two.
I suggest reduce it to 10 seconds, and heretofore, in worse case scenario, the nodes won't start querying the latest blocks.

[kehiy]

that's make sense, I will reduce it to 10 seconds.