superwow: move into its own module

Moving superwow integration from thirdparty into a seperate module.
It's a client mod, not an addon and therefore should not bloat the
thirdparty section that is already huge enough.

It was a mistake to treat it as an addon-compat in first place.

Now having it as a seperate module also allows it to grow better
over time as new SuperWoW features are integrated into pfUI.

modules/superwow.lua

@@ -0,0 +1,49 @@
+-- Compatibility layer to use castbars provided by SuperWoW:
+-- https://github.com/balakethelock/SuperWoW
+pfUI:RegisterModule("superwow", "vanilla", function ()
+  local unitcast = CreateFrame("Frame")
+  unitcast:RegisterEvent("UNIT_CASTEVENT")
+  unitcast:SetScript("OnEvent", function()
+    if arg3 == "START" or arg3 == "CAST" or arg3 == "CHANNEL" then
+      -- human readable argument list
+      local guid = arg1
+      local target = arg2
+      local event_type = arg3
+      local spell_id = arg4
+      local timer = arg5
+      local start = GetTime()
+
+      -- get spell info from spell id
+      local spell, icon, _
+      if SpellInfo and SpellInfo(spell_id) then
+        spell, _, icon = SpellInfo(spell_id)
+      end
+
+      -- set fallback values
+      spell = spell or UNKNOWN
+      icon = icon or "Interface\\Icons\\INV_Misc_QuestionMark"
+
+      -- add cast action to the database
+      if not libcast.db[guid] then libcast.db[guid] = {} end
+      libcast.db[guid].cast = spell
+      libcast.db[guid].rank = nil
+      libcast.db[guid].start = GetTime()
+      libcast.db[guid].casttime = timer
+      libcast.db[guid].icon = icon
+      libcast.db[guid].channel = event_type == "CHANNEL" or false
+
+      -- write state variable
+      superwow_active = true
+    elseif arg3 == "FAIL" then
+      local guid = arg1
+
+      -- delete all cast entries of guid
+      libcast.db[guid].cast = nil
+      libcast.db[guid].rank = nil
+      libcast.db[guid].start = nil
+      libcast.db[guid].casttime = nil
+      libcast.db[guid].icon = nil
+      libcast.db[guid].channel = nil
+    end
+  end)
+end)