Fix DOS to UNIX conversion

Original method corrupted files by deleting all leading capital 'M' on each line, not just ^M line endings.

src/install_nquakesv.sh

@@ -430,7 +430,7 @@ nqnecho "* Removing distribution files..."
 # Convert DOS files to UNIX
 nqnecho "* Converting DOS files to UNIX..."
 for file in $(find ${directory} -iname "*.cfg" -or -iname "*.txt" -or -iname "*.sh" -or -iname "README"); do
-  [ -f "${file}" ] && sed -i 's/^M//g' ${file}
+  [ -f "${file}" ] && sed -i 's/^M$//' ${file}
 done
 nqecho "done"