[css2] Added (missing) transparent to border color properties

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extra : convert_revision : svn%3A73dc7c4b-06e6-40f3-b4f7-9ed1dbc14bfc/trunk%401731

Author: ianbjacobs

css2/properties/properties.db

@@ -11,7 +11,7 @@ containing block ;; visual  */
 /* border-top-width border-right-width border-bottom-width border-left-width;; <border-width> | inherit;; medium;; *;; no;; N/A ;; visual */
 /* border-width;; <border-width>{1,4} | inherit;; see individual properties;; *;; no;; N/A ;; visual  */
 
-/* border-top-color border-right-color border-bottom-color border-left-color;; <color> | inherit;; the value of the 'color' property;; *;; no;; N/A ;; visual  */
+/* border-top-color border-right-color border-bottom-color border-left-color;; <color> | transparent | inherit;; the value of the 'color' property;; *;; no;; N/A ;; visual  */
 /* border-color;; <color>{1,4} | transparent | inherit;; see individual properties;; *;; no;; N/A ;; visual  */
 
 /* border-top-style border-right-style border-bottom-style border-left-style;; <border-style> | inherit;; none;; *;; no;; N/A ;; visual  */