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/TriggerBase.lua

@@ -0,0 +1,37 @@
+local TriggerBase = {}
+
+function TriggerBase:new(o)
+	o = o or {}
+	o.id = o.id or {}
+	o.fn = o.fn or {}
+	o.y = o.y or {}
+	o.e = o.e or {}
+
+	setmetatable(o, self)
+	self.__index = self
+	return o
+end
+
+function TriggerBase:call(event)
+	self.ERM.activeEvent = event
+	self.ERM.activeTrigger = self
+	for _, fn in ipairs(self.fn) do
+		fn(self.e, self.y)
+	end
+	self.ERM.activeTrigger = nil
+	self.ERM.activeEvent = nil
+end
+
+function TriggerBase:addHandler(fn)
+	table.insert(self.fn, fn)
+end
+
+function TriggerBase:checkSub(sub, sub_name)
+	if type(sub) == "string" then
+		error(sub_name .. " subscription failed: "..sub)
+	elseif type(sub) ~= "userdata" then
+		error(sub_name .. " subscription failed")
+	end
+end
+
+return TriggerBase