Generation of text and html trees with pyang to navigate through the IM

Change-Id: I8770e13e69f50adb948494ca6bbc9edce0c4e56c
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/.gitignore b/.gitignore
index 0025eee..66f7158 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,6 +6,7 @@
 *egg-info
 *.gz
 osm_im
+osm_im_trees
 pyangbind
 pyang
 dists