Move Known Issues section to docs folder

The known issues section should be placed in its own file for
future additions.  It was also included a validation that
prevents the auto update feature of vagrant-vbguest plugin.

Change-Id: Ibdbd89c15b657b11b346c2cbcc084176f82d8102
Signed-off-by: Victor Morales <victor.morales@intel.com>
Issue-Id: INT-98
diff --git a/bootstrap/vagrant-onap/doc/source/index.rst b/bootstrap/vagrant-onap/doc/source/index.rst
index 2dacced..af5777c 100644
--- a/bootstrap/vagrant-onap/doc/source/index.rst
+++ b/bootstrap/vagrant-onap/doc/source/index.rst
@@ -18,5 +18,6 @@
    :maxdepth: 2
 
    Installation Guide <install/index>
+   Known Issues <install/known_issues>
    Advanced Features <features/features>