Bazel: Add dummy BUILD file in lib/jgit

Fixes the error:

  Unable to load package for '//lib/jgit:jgit.bzl':
  BUILD file not found on package path.

Change-Id: Ic3506f8777fc1875f00e295bd1775c774b56ef19
diff --git a/lib/jgit/BUILD b/lib/jgit/BUILD
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/lib/jgit/BUILD