move session library implementation to a separate module

res/modules/internal/session.lua

@@ -0,0 +1,17 @@
+local entries = {}
+local this = {}
+
+function this.get_entry(name)
+    local entry = entries[name]
+    if entry == nil then
+        entry = {}
+        entries[name] = entry
+    end
+    return entry
+end
+
+function this.reset_entry(name)
+    entries[name] = nil
+end
+
+return this

res/scripts/stdlib.lua

@@ -345,23 +345,7 @@ function gui.template(name, params)
     return text
 end
 
-session = {
-    entries={}
-}
-
-function session.get_entry(name)
-    local entry = session.entries[name]
-    if entry == nil then
-        entry = {}
-        session.entries[name] = entry
-    end
-    return entry
-end
-
-function session.reset_entry(name)
-    session.entries[name] = nil
-end
-
+session = require "core:internal/session"
 stdcomp = require "core:internal/stdcomp"
 entities.get = stdcomp.get_Entity
 entities.get_all = function(uids)