.gitignore: add visual studio IDE files and OS X .DS_Store files

https://bugzilla.gnome.org/show_bug.cgi?id=667899
diff --git a/.gitignore b/.gitignore
index 98a665a..36b89c8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -54,3 +54,11 @@
 tmp-orc.c
 gst*orc.h
 tests/check/orc
+
+Build
+*.user
+*.suo
+*.ipch
+*.sdf
+*.opensdf
+*.DS_Store
\ No newline at end of file