Fix .gitattributes

This behavior should check out files in the native line ending depending
on your platform.

.gitattributes

@@ -1,7 +1,9 @@
 # This won't normalise line endings, but it will ensure that merge drivers use CRLF
 * -text eol=crlf
 
-*.cs eol=crlf
+*.cs text=auto
+*.csproj text=auto
+*.sln text=auto
 
 # Currently in-use binary file extensions
 *.blend  binary