ui: Make sure sendcoinsentry signals only connected once
ui: Make sure sendcoinsentry signals only connected once

Move signal connections to constructor where possible.

(cherry picked from commit 29eaa316944477af538b75b439a49ee1a9fc2f2a)

reddcoin-project/reddcoin,reddcoin-project/reddcoin,reddcoin-project/reddcoin,reddcoin-project/reddcoin,reddcoin-project/reddcoin,reddcoin-project/reddcoin