Add a Unix shell script to set file types

Because the previous README instructions did not specify *.sh files as
exempt from line-ending filtering, I have added SetFileTypes.sh as one-
liner.

Misc/SetFileTypes.sh

@@ -0,0 +1 @@
+cd "`dirname "$0"`"; cd ..; find . -type f -not -path '*/.*' -not -ipath './BuildResults/*' -not -ipath './Tools/*' -exec SetFile -t 'TEXT' -c 'MPS ' {} \;; find Tools -type f -not -path '*/.*' \( -ipath '*.c' -o -ipath '*.h' -o -ipath '*.make' \) -exec SetFile -t 'TEXT' -c 'MPS ' {} \;; find BuildResults -type f -not -path '*/.*' \( -ipath '*.o' -o -ipath '*.lib' \) -exec SetFile -t 'OBJ ' -c 'MPS ' {} \;; find . -type f -not -path '*/.*' \( -ipath '*.rsrc' -o -iname GoNativeResources \) -exec SetFile -t 'rsrc' -c 'RSED' {} \;

README.md

@@ -18,13 +18,21 @@ Append this to `.git/info/attributes`:
 	* filter=maclines
 	*.lib -filter
 	*.o -filter
+	*.sh -filter
 	.gitignore -filter
 
 Finally, do a once-off "re-smudge":
 
 	rm -rf ../mac-rom/*
 	git checkout .
 
+Setting type and creator codes
+------------------------------
+
+Some MPW Tools require their input files to have the correct Mac OS file type ("TEXT" or "OBJ "), but Git does not save Mac OS type and creator codes. This shell script will correct the file types in a freshly cloned repo:
+
+	sh Misc/SetFileTypes.sh
+
 Building
 --------
 This code is built with the [Macintosh Programmer's Workshop](https://en.wikipedia.org/wiki/Macintosh_Programmer%27s_Workshop) (MPW), which runs on the Classic Mac OS. To satisfy the memory requirements of the build process, the MPW Shell should get a memory partition of at least 16 MB. Once you have MPW set up, the build process is not particularly fussy.