Make it easy to generate necessary artifacts to run enemize-rs.

Maybe these files could be committed? It's not like they'll change very
often. But maybe there's copyrighted material in them I haven't noticed.

.gitignore

@@ -1,3 +1,4 @@
 /target
-exported_symbols.txt
+asar_symbols.txt
-patchData.json
+base_patch.json
+enemizer_base_patch.json

prepare.sh

@@ -0,0 +1,8 @@
+#!/bin/sh
+
+if [[ ! -s base_patch.json || ! -s asar_symbols.txt ]]; then
+cargo run -p bin_comp -- assembly/src/main.asm base_patch.json asar_symbols.txt
+fi
+if [[ ! -s enemizer_base_patch.json ]]; then
+cargo run -p base_patch_generator -- "$1" base_patch.json asar_symbols.txt enemizer_base_patch.json
+fi