Clean up and throw exceptions in Map actions

[lexiccn]

This is a very opinionated PR that you may not agree with entirely

Changes:

• Throw RuntimeException in any MapAction constructor if Town Costs Icon URL is invalid or it does not register (for Dynmap; even if it would not be used - felt this was a nonissue)
• Remove equality checks before setting Marker colour in Pl3xMap v3 and Dynmap actions (in BlueMap this is in the other PR as it was part of that first)
• Catch RuntimeException on a per-map basis in TownyProvinces, do not catch any other Exception (Makes a clear divide between intended and unintended exceptions which I felt should be allowed to propagate)

[lexiccn]

Closing this to merge with my integration reloading branch to avoid conflicts; will make some changes to this content also