Add scoring sheet

At the DefCore sprint in Austin last week we agreed on a format
for moving scoring activities into Gerrit.  This should make
discussion outside of meetings easier to accomplish and make
use of the same toolchain we use for other activities (as well
as having the benefit of being accessible to folks in countries
that cannot access Google Docs where working materials were
formerly kept).

This patch creates a directory for working materials and populates
it with an empty scoring sheet.  We will add capabilties and
scores to it in future patches.

Change-Id: I42dfe410edf4412853b9f976eaf017b90c1a8a51

working_materials/scoring.txt

@@ -0,0 +1,19 @@
+DefCore Scoring Worksheet
+=========================
+
+This file is used to maintain capabilities scoring for DefCore.
+It is considered "working materials" under the 2015B process and
+is not an authoritative, Board-approved source of information
+as to which capabilities are required for a particular Guideline.
+Rather, it is a point-in-time listing used by DefCore Committee
+members while determining which capabilities may be included in
+a future Guideline.  Each line takes the following form:
+
+Capability Name: [Widely Deployed,Used By Tools,Used by Clients],
+                 [TC Future Direction, Complete, Stable],
+                 [Discoverable, Doc'd, Core in Last Release],
+                 [Foundational, Atomic, Proximity],
+                 [Non-Admin]
+
+Possible scores: 0, 1, ? (not scored yet or needs discussion)
+