PON requirement docs and seq diagrams

Please review and comment.

Change-Id: Iccec623e25bd723816c235cd4dd1a3b6d54e7d85
diff --git a/docs/pon-requirements/olt-states.block b/docs/pon-requirements/olt-states.block
new file mode 100644
index 0000000..8e2c71d
--- /dev/null
+++ b/docs/pon-requirements/olt-states.block
@@ -0,0 +1,22 @@
+blockdiag {
+
+  // States
+  N1 [label = Not-exist, shape = beginpoint];
+  N2 [label = Not-exist, shape = beginpoint];
+  Discovered [shape = ellipse];
+  Pre-provisioned [shape = ellipse];
+  Activating [shape = ellipse];
+  Active [shape = ellipse, color = "#80ff80"];
+  Failed [shape = ellipse, color = "#ff8080"];
+  TBD [shape = ellipse, stacked];
+
+  // Transients
+  N1 -> Pre-provisioned;
+  N2 -> Discovered;
+  Pre-provisioned -> Activating;
+  Discovered -> Activating;
+  Activating -> Active;
+  Activating -> Failed [folded];
+  Active -> Failed [folded];
+
+}