documentation for using guard in the PDP

Added guardpdp.rst and minor updates to other documentation.
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Change-Id: If0d430cdff3b9b1700b773b78c3d951698609714
Issue-Id: POLICY-335
Signed-off-by: Saryu Shah <ss3917@att.com>
diff --git a/docs/platform/architecture.rst b/docs/platform/architecture.rst
index d9ce3c8..28215de 100644
--- a/docs/platform/architecture.rst
+++ b/docs/platform/architecture.rst
@@ -96,3 +96,5 @@
 Policy writers can define attributes so that policy events or requests self-indicate their scope. The scope is then examined by a suitable function and subsequently acted upon accordingly. Policy decisions and enforcement functions can self-indicate their scope of decision-making, enforcement, or other capabilities. Virtual functions can be automatically attached to the appropriate POLICY Framework and distribution mechanisms.
 
 
+End of Document
+