Add support for Plugin load order to XML

[barkermn01]

Having built Ultrasound to support plugins loaded via 7th Heaven, the Plugins for Ultrasound must be loaded before Ultrasound Plugin is loaded.

So this is a feature request to support a LoadPriority for plugins. and if no priority is specified it defaults to 1 so plugins that need to load before others can use 0.

E.G

  <LoadLibrary>VoiceHook.dll</LoadLibrary>
  <LoadPlugin Priotiy=1>Ultrasound7H.dll</LoadPlugin>
  <LoadPlugin Priority=0>UltrasoundInputHooker.dll</LoadPlugin> 

Instead of

  <LoadLibrary>VoiceHook.dll</LoadLibrary>
  <LoadPlugin>UltrasoundInputHooker.dll</LoadPlugin> 
  <LoadPlugin>Ultrasound7H.dll</LoadPlugin>