(Git)ignore all of /net. Works around issue: gclient sync, git clean -df, gclient runhooks -> failure (regression in r4466).

BUG=N/A
R=andrew@webrtc.org, fischman@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/9689004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5688 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/.gitignore b/.gitignore
index f944a5b..a7cb261 100644
--- a/.gitignore
+++ b/.gitignore
@@ -40,7 +40,7 @@
 /chromium_gn
 /google_apis/build
 /gyp-mac-tool
-/net/third_party/nss/
+/net
 /out
 /resources/*.*
 /resources/*/*.*