[css2] Added so that sample property can be inserted in document without including it in prop index or index

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extra : convert_revision : svn%3A73dc7c4b-06e6-40f3-b4f7-9ed1dbc14bfc/trunk%401318

Author: ianbjacobs

css2/properties/sample.db

@@ -0,0 +1,8 @@
+/* property-name;;
+   legal values & syntax;;
+   initial value;;
+   elements this property applies to;;
+   whether the property is inherited;;
+   how percentage values are interpreted;;
+   which media groups the property applies to
+*/