Add a way to easily split DYN coins in the GUI (Dynode Setup)

[LordDarkHelmet]

Adding a feature on the GUI that allows a user to split coins. This will make it easier for users to setup multiple Dynodes.

Danmoore on the Discord server wanted to setup multiple Dynodes. It would make the process easier if he was able to split coins via sendmany from the GUI.

On that note It may be time to implement a Dynode setup GUI within the wallet. For example something like this from Dash:

https://docs.dash.org/en/stable/masternodes/setup.html

[AmirAbrams]

It looks like the code for that tool is in this repo: https://github.com/Bertrand256/dash-masternode-tool