Entities redesign and a few ERM features

* Made most Handlers derived from CHandlerBase and moved service API there.
* Declared existing Entity APIs.
* Added basic script context caching
* Started Lua script module
* Started Lua spell effect API
* Started script state persistence
* Started battle info callback binding
* CommitPackage removed
* Extracted spells::Caster to own header; Expanded Spell API.
* implemented !!MC:S, !!FU:E, !!FU:P, !!MA, !!VR:H, !!VR:C
* !!BU:C, !!BU:E, !!BU:G, !!BU:M implemented
* Allow use of "MC:S@varName@" to declare normal variable (technically v-variable with string key)
* Re-enabled VERM macros.
* !?GM0 added
* !?TM implemented
* Added !!MF:N
* Started !?OB, !!BM, !!HE, !!OW, !!UN
* Added basic support of w-variables
* Added support for ERM indirect variables
* Made !?FU regular trigger
* !!re (ERA loop receiver) implemented
* Fixed ERM receivers with zero args.

scripts/lib/erm/DO.lua

@@ -0,0 +1,55 @@
+local ReceiverBase = require("core:erm.ReceiverBase")
+
+local DO = ReceiverBase:new()
+
+function DO:new(ERM, fun, start, stop, inc)
+	assert(fun and start and stop and inc, "!!DO requires 4 arguments")
+	return ReceiverBase.new(self,
+	{
+		ERM=ERM,
+		fun=fun,
+		start=start,
+		stop=stop,
+		inc=inc,
+	})
+end
+
+function DO:P(x, ...)
+	local argc = select('#', ...)
+	local newx = {}
+	local ret = {}
+
+	do
+		local __iter, limit, step = tonumber(self.start), tonumber(self.stop), tonumber(self.inc)
+
+		while (step > 0 and __iter <= limit) or (step <= 0 and __iter >= limit) do
+
+			for idx = 1, argc do
+				local v = select(idx, ...)
+
+				if v ~= nil then
+					newx[tostring(idx)] = v
+				end
+			end
+
+			newx['16'] = __iter
+			self.ERM:callFunction(self.fun, newx)
+			__iter = newx['16']
+			__iter = __iter + step
+		end
+	end
+
+	for idx = 1, argc do
+		local v = select(idx, ...)
+		if v == nil then
+			ret[idx] = newx[tostring(idx)]
+		else
+			ret[idx] = nil
+		end
+	end
+
+	return unpack(ret)
+end
+
+
+return DO