Enable motd on non-pocket and command computers

- I'm excluding pocket computers, as they have such a tiny screen I'm
   not sure the screen estate is worth it.
   Pocket computers /generally/ aren't people's starter machine, so I
   think this is fine.
 - Prune the motd list, and try to make them a little shorter. I think
   this list is more of the interesting ones. We can modify this list in
   the future, as we get more feedback.[^1]
 - Also fix paint/edit not adding an extension when they should. This
   was caused by the settings rewrite, as the explicitly provided
   default shadowed the one provided by bios.lua.

[^1]: ~5 months ago I asked for some feedback about enabling motds by
      default. I only got something constructive back today >_>.

src/main/resources/assets/computercraft/lua/bios.lua

@@ -923,7 +923,7 @@ settings.define("list.show_hidden", {
 })
 
 settings.define("motd.enable", {
-    default = false,
+    default = pocket == nil,
     description = "Display a random message when the computer starts up.",
     type = "boolean",
 })

src/main/resources/assets/computercraft/lua/rom/motd.txt

@@ -1,43 +1,23 @@
-View the source code at https://github.com/SquidDev-CC/CC-Tweaked
+Please report bugs at https://github.com/SquidDev-CC/CC-Tweaked. Thanks!
 View the documentation at https://wiki.computercraft.cc
-Visit the forum at https://forums.computercraft.cc
+Show off your programs or ask for help at our forum: https://forums.computercraft.cc
 You can disable these messages by running "set motd.enable false".
-You can create directories with "mkdir".
-Want to see hidden files? Run "set list.show_hidden true".
-Run "list" or "ls" to see all files in a directory.
-You can delete files and directories with "delete" or "rm".
 Use "pastebin put" to upload a program to pastebin.
-Use "pastebin get" to download a program from pastebin.
-Use "pastebin run" to run a program from pastebin.
 Use the "edit" program to create and edit your programs.
-You can copy files with "copy" or "cp".
-You can use "wget run <url>" to run a program from the internet.
 You can use "wget" to download a file from the internet.
 On an advanced computer you can use "fg" or "bg" to run multiple programs at the same time.
-Use "type" to see if a path is a file or a directory.
-Get a list of all programs with "programs".
 Use an advanced computer to use colours and the mouse.
 With a speaker you can play sounds.
-Use "motd" to print the Message of the Day.
-You can disable the startup from a computer with "set shell.allow_startup false".
-You can disable the startup from a disk with "set shell.allow_disk_startup false".
 Programs that are placed in the "startup" folder in the root of a computer are started on boot.
 Use a modem to connect with other computers.
 With the "gps" program you can get the position of a computer.
 Use "monitor" to run a program on a attached monitor.
-View all attached peripherals with "peripherals".
+Don't forget to label your computer with "label set".
-Use "time" to see the in-game time.
-You can set the label of a computer with "label set".
-A computer needs a label to keep its files if it is destroyed.
-You can disable auto completion in the shell with "set shell.autocomplete false".
-You can disable auto completion in edit with "set edit.autocomplete false".
 Feeling creative? Use a printer to print a book!
-Files beginning with a "." character are hidden from "list" by default.
+Files beginning with a "." are hidden from "list" by default.
 Running "set" lists the current values of all settings.
-Some programs are only available on advanced computers, turtles, pocket computers, or command computers.
+Some programs are only available on advanced computers, turtles, pocket computers or command computers.
-The "equip" and "unequip" programs let you add or remove supported upgrades from a turtle or pocket computer without crafting.
+The "equip" programs let you add upgrades to a turtle without crafting.
-You can change the color of a disk by crafting it with dye.
+You can change the color of a disk by crafting or right clicking it with dye.
-Right-clicking a turtle with a dye changes its color.
 You can print on a printed page again to get multiple colors.
-Holding the Control and T keys terminates the running program.
+Holding the Ctrl and T keys terminates the running program.
-Holding Control and S or R shuts down or reboots the computer you are using.

src/main/resources/assets/computercraft/lua/rom/programs/edit.lua

@@ -15,7 +15,7 @@ end
 
 -- Create .lua files by default
 if not fs.exists(sPath) and not string.find(sPath, "%.") then
-    local sExtension = settings.get("edit.default_extension", "")
+    local sExtension = settings.get("edit.default_extension")
     if sExtension ~= "" and type(sExtension) == "string" then
         sPath = sPath .. "." .. sExtension
     end

src/main/resources/assets/computercraft/lua/rom/programs/fun/advanced/paint.lua

@@ -46,7 +46,7 @@ end
 
 -- Create .nfp files by default
 if not fs.exists(sPath) and not string.find(sPath, "%.") then
-    local sExtension = settings.get("paint.default_extension", "")
+    local sExtension = settings.get("paint.default_extension")
     if sExtension ~= "" and type(sExtension) == "string" then
         sPath = sPath .. "." .. sExtension
     end