Update Bucklets to get new Eclipse version

Because Eclipse outputs moved to eclipse-out, DevServer may be loaded
from either buck-out or eclipse-out. Tweak the heuristic for finding
the source root: look for a directory containing .buckconfig.

Change-Id: Ibf04ced29d48c70ffa76fd6d6fb4bf5900c785db

.gitignore

diff --git a/.gitignore b/.gitignore
index cd7c29f..8b1fe53 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,5 +2,6 @@
 /.project
 /.settings
 /buck-out
+/eclipse-out
 /gitiles.config
 /.buckd