Prevent /up griefing, add /ackey, minor tweaks

Dunno why its posting 'changes' in main.py tho

main.py

@@ -38,8 +38,8 @@ shared["load_modules"] = [
     "adminchat",
     # Adds /badge, allows to give players achievements
     "badges",
-   	# Adds a few block placement corrections/mods
-   	"blockplacemods",
+    # Adds a few block placement corrections/mods
+    "blockplacemods",
     # Adds /calc, toggles automatic solving of Math expressions in chat
     "calc",
     # Plugin to locate laggy chunks. /lc <n> lists chunks with more than n entities
@@ -87,4 +87,4 @@ for module in shared["load_modules"]:
         info("Module %s loaded." % module)
     except:
         error("Failed to import module %s:" % module)
-        error(print_traceback())
+        error(print_traceback())