.gitattributes: CRLF for all files that need them

Improvements of the CRLF handling:
When a file is checked out on a drive shared with Linux or MacOS,
those OS have different default line endings.
Windows uses CRLF, and Linux/Mac use LF.

To be able to checkout files under Linux/Mac and to get the same
result, mark all known file types with eol=CRLF

.gitattributes

@@ -1,6 +1,18 @@
 # end of line conversion CLRF -- LF
 # Default is auto
 *              text=auto
-#
-# Shell scripts must be line feed
+
+# Hidden .git files: CRLF for convenience
+.gitattributes text eol=crlf
+.gitignore     text eol=crlf
+
+# Shell scripts must be LF
 *.sh           text eol=lf
+
+# Tc files must be CRLF
+*.plcproj      text eol=crlf
+*.Tc*          text eol=crlf
+*.tsproj       text eol=crlf
+*.txt          text eol=crlf
+*.xml          text eol=crlf
+*.xti          text eol=crlf