Update .gitattributes

- Append Windows Icon extension.
- Append Windows Cursor extension.
- Append Windows Animated Cursor extension.

Author: frg2089

.gitattributes

@@ -133,3 +133,6 @@
 *.pnm               filter=lfs diff=lfs merge=lfs -text
 *.wbmp              filter=lfs diff=lfs merge=lfs -text
 *.exr               filter=lfs diff=lfs merge=lfs -text
+*.ico               filter=lfs diff=lfs merge=lfs -text
+*.cur               filter=lfs diff=lfs merge=lfs -text
+*.ani               filter=lfs diff=lfs merge=lfs -text