Add channel upgrade init and try tx commands

[seanchen1991]

Summary

As part of the work of implementing channel upgradability in Hermes, we'll need to add hermes tx chan-upgrade-init and hermes tx chan-upgrade-try CLI commands, similar to the hermes tx chan-open-* family of commands.

Part of this work also includes defining the message types needed in order for these commands to work.

[ljoss17]

init has not been implemented as it requires a governance proposal.
try Done by #3228