Remove redundant entries from .gitignore

Files/folders related to buck and maven no longer need to be
ignored.

Change-Id: Ic65ff0d9503c6c7484edcc059cbf0f78a6d70f33
diff --git a/.gitignore b/.gitignore
index b4277e3..499784b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,9 +1,3 @@
-/.buckversion
-/.buckd
-/.watchmanconfig
-/buck-out
-/bucklets
-/target
 /.classpath
 /.project
 /.settings/org.maven.ide.eclipse.prefs