adding loadorder to savegame

work_files/DataFormats/SAVE_FORMAT.md

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+## Introduction
+
+On the main game, any player can access any generated worlds, and thus players data and worlds are saved separately.
+
+The main game directory is composed of following directories:
+
+```
+.Terrarum
++ Players
+  - "${PlayerName}-${UUID}", TVDA {
+      [-1] player JSON,
+      [-2] spritedef,
+      [-3] !optional! spritedef-glow,
+      [-4] loadOrder.txt
+      [-1025] !optional! sprite-bodypart-name-to-entry-number-map.properties,
+      [-1026] !optional! spriteglow-bodypart-name-to-entry-number-map.properties,
+      [1+] !optional! bodyparts tga.gz
+    }
+    *if file -1025 is not there, read bodyparts from assets directory
+    *optionally encrypt the files other than -1
+    *disk name is player's name encoded in UTF-8
++ Shared
+  - <e.g. Disk GUID>, TEVD { * }
+  - <this directory can have anything>
++ Worlds
+  - "${WorldName}-${UUID}", TVDA {
+      [-1] world JSON with Player Data,
+      [actorID] actors (mainly fixtures) JSON,
+      [0x1_0000_0000L or (layerNumber shl 24) or chunkNumber] chunk data,
+      [-2] screenshot.tga.gz taken by the last player
+      [-4] loadOrder.txt
+    }
+    *disk name is world's name encoded in UTF-8
+```
+
+(TEVD stands for Terrarum Virtual Disk spec version 3, TVDA stands for spec version 254; both have MAGIC header of `TEVd`)
+
+Do not rely on filename to look for a world; players can change the filename
+
+## Handling The Player Data
+
+Some of the "player assets" are stored to the world, such assets include:
+- Physical Status (last position and size as in scale)
+- Inventory (instance of ActorInventory)
+- Actorvalues (only on Multiplayer)
+
+### Loading Procedure
+
+1. Load the Actor completely first
+2. Load the World
+3. Overwrite player data with the World's 
+   
+If the World has the Actorvalue, World's value will be used; otherwise use incoming Player's
+
+Multiplayer world will initialise Actorvalue pool using incoming value -- or they may choose to use
+their own Actorvalue called "gamerules" to either implement their own "gamemode" or prevent cheating)
+
+For Singleplayer, only the xy-position is saved to the world for later load.
+
+Worlds must overwrite new Actor's position to make them spawn in right place.
+
+### Remarks
+
+Making `inventory` transient is impossible as it would render Storage Chests unusable.
+
+## Prerequisites
+
+1. Player ID must not be strictly 9545698 (0x91A7E2)
+    1. Use classname `net.torvald.terrarum.modulebasegame.gameactors.IngamePlayer` to check
+2. Each World and Player has to be uniquely identifiable via GUID
+3. `ActorNowPlaying` must be drawn on top of other actors of same RenderOrder
+
+## To-dos After the Initial Implementation
+
+1. Modify Savegame Crackers and Disk Crackers to work with the new scheme
+2. Create Player Creator Tool for avatar-makers
+
+## Goals
+
+1. Allow multiple players share the same world
+2. Make multiplayer possible
+3. Make Players distributable (like VRChat avatars)