Remove unused submodules (#226)

* Update .gitmodules

* Delete import

.gitmodules

@@ -1,9 +1,3 @@
-[submodule "tools/asm-differ"]
-	path = tools/asm-differ
-	url = https://github.com/simonlindholm/asm-differ
-[submodule "tools/decomp-permuter"]
-	path = tools/decomp-permuter
-	url = https://github.com/simonlindholm/decomp-permuter
 [submodule "doxygen-awesome-css"]
 	path = doxygen-awesome-css
 	url = https://github.com/jothepro/doxygen-awesome-css.git

import

@@ -1,7 +0,0 @@
-#!/bin/bash
-
-# note, this quick hack only works with five arguments.
-# if you're trying to use six arguments, you need to add another `$6` etc.
-
-python3 tools/decomp-permuter/import.py $1 $2 $3 $4 $5
-