fix ls exit code when piping

src/main/resources/assets/opencomputers/loot/openos/bin/ls.lua

@@ -4,7 +4,10 @@ local ok, why = pcall(function(...)
   return loadfile("/opt/core/full_ls.lua", "bt", _G)(...)
 end, ...)
 
-if not ok then 
+if not ok then
+  if type(why) == "table" and why.code == 0 then
+    return
+  end
   io.stderr:write((why or "") .. "\nFor low memory systems, try using `list` instead\n")
   return 1
 end

src/main/resources/assets/opencomputers/loot/openos/boot/02_os.lua

@@ -2,7 +2,6 @@ local computer = require("computer")
 local event = require("event")
 local fs = require("filesystem")
 local shell = require("shell")
-local unicode = require("unicode")
 local process = require("process")
 
 local function env()