Made Histrory Length a EnvVar

Well, there is it!

src/main/resources/assets/opencomputers/loot/OpenOS/bin/sh.lua

@@ -7,6 +7,14 @@ local shell = require("shell")
 local term = require("term")
 local text = require("text")
 
+local function getHistSize()
+  if os.getenv("HISTSIZE") then
+    return os.getenv("HISTSIZE")
+  else
+    return 10
+  end
+end
+
 local function expand(value)
   local result = value:gsub("%$(%w+)", os.getenv):gsub("%$%b{}",
     function(match) return os.getenv(expand(match:sub(3, -2))) or match end)
@@ -165,7 +173,7 @@ if #args == 0 and (io.input() == io.stdin or options.i) and not options.c then
         term.write("exit\n")
         return -- eof
       end
-      while #history > 20 do
+      while #history > getHistSize() do
         table.remove(history, 1)
       end
       command = text.trim(command)

src/main/resources/assets/opencomputers/loot/OpenOS/boot/01_os.lua

@@ -16,6 +16,7 @@ local env = {
   SHELL="/bin/sh",
   TMP="/tmp", -- Depricated
   TMPDIR="/tmp"
+  HISTSIZE=10
 }
 
 os.execute = function(command)