Don't shut down completely if compatible mob library not found

TODO.txt

@@ -1,5 +1,4 @@
 
 TODO:
 - port to mobkit
-- don't shut down completely if compatible mob library not found
 - add setting to change mob library preference order

init.lua

@@ -3,30 +3,6 @@ skeleton = {}
 skeleton.modname = core.get_current_modname()
 skeleton.modpath = core.get_modpath(skeleton.modname)
 
--- support mob libraries in order of preference
-local mob_libs = {
-	"mobs",
-	"cmer",
-	"creatures",
-}
-
-for _, ml in ipairs(mob_libs) do
-	if core.get_modpath(ml) then
-		skeleton.lib = ml
-		break
-	end
-end
-
--- check for compatible library
-if not skeleton.lib then
-	error("a compatible mob library was not found, please install one of the following: "
-		.. table.concat(mob_libs, ", "))
-end
-
-if skeleton.lib == "creatures" then
-	skeleton.lib = "cmer"
-end
-
 function skeleton.log(lvl, msg)
 	if not msg then
 		msg = lvl
@@ -43,6 +19,33 @@ function skeleton.log(lvl, msg)
 end
 
 
+-- support mob libraries in order of preference
+local mob_libs = {
+	"mobs",
+	"cmer",
+	"creatures",
+}
+
+for _, ml in ipairs(mob_libs) do
+	if core.get_modpath(ml) then
+		skeleton.lib = ml
+		break
+	end
+end
+
+-- check for compatible library
+if not skeleton.lib then
+	skeleton.log("error", "Could not load. A compatible mob library was not found. Please install one of the following: "
+		.. table.concat(mob_libs, ", "))
+	skeleton = nil
+	do return end
+end
+
+if skeleton.lib == "creatures" then
+	skeleton.lib = "cmer"
+end
+
+
 local scripts = {
 	"settings",
 	"entity",