Slightly tweak error when unable to bind port

A slight improvement over 2d2d8fae3d8bc4e82dc631d93c6e19f954bbee04 -- we don't know that it's the daemon, it could be the GUI.
Adjust branding in datadir lock error message
Merge pull request #3806

9e2872c Adjust branding in datadir lock error message (Michagogo)
d30d379 Slightly tweak error when unable to bind port (Michagogo)