cli product version number behind tags

[chappjc]

https://github.com/btcsuite/btcwallet/blob/40518d709db8627381a934ce71468c6507e4cfc3/version.go#L19-L21

Before next tag, would be ideal to bump the hard-coded version for the cli app. It's fairly inconsequential for go consumers, but it's nice when running btcwallet to have it reflect the general dev cycle that it was build from.

I had mentioned this before, but wanted to make an issue to track it. :smile:

[Roasbeef]

Good idea, we don't use the direct CLI much ourselves, but we should def start to update it properly each time we do a new tag.