Add .gitignore entry for Ghidra project

May make it an official recommendation to have a project named "JSRF"
here.

decompile/objdiff.json

@@ -16,10 +16,10 @@
         "source_path": "src/JSRF/Jet2.cpp"
       },
       "symbol_mappings": {
-        "?main_funcinfo@@3UFuncInfo@@A": "$T1112",
-        "?main_handler@@YAXPAUEHExceptionRecord@@PAKPAXPAU_xDISPATCHER_CONTEXT@@@Z": "$L1116",
-        "?main_handler_unwind1@@YAXXZ": "$L1108",
-        "?main_unwindmap@@3PAUUnwindMapEntry@@A": "$T1118",
+        "?main_funcinfo@@3UEHFuncInfo@@A": "$T1130",
+        "?main_handler@@YAXPAUExceptionRecord@@PAKPAXPAUEHDispatcherContext@@@Z": "$L1134",
+        "?main_handler_unwind1@@YAXXZ": "$L1126",
+        "?main_unwindmap@@3PAUEHUnwindMapEntry@@A": "$T1136",
         "[.rdata-0]": "[.xdata$x-0]"
       }
     },

ghidra/.gitignore

@@ -1 +1,4 @@
 jsrf.h
+
+# In case you'd like to put your Ghidra project here
+project

ghidra/delink.sh

@@ -67,8 +67,8 @@ delink() {
 # $5: Output path (inside decompile/target/)
 	# Call the right script depending on whether we're on Windows
 	# (this seems like the most reliable method I can find for POSIX sh)
-	if [ -n "$WINDIR" ]; then suffix=.bat
-	else                      suffix=
+	if [ -n "${WINDIR-}" ]; then suffix=.bat
+	else                         suffix=
 	fi
 
 	# POSIX compatibility layers for Windows (like in git bash) will