add key value pair as a Block Additional Mapping

Author: dericed

block_additional_mappings/key_value.md

@@ -0,0 +1,17 @@
+## Key Value Pair
+
+### Key Value Pair Description
+
+The Block Additional Mapping for a `Key Value Pair` provides a generic method store data with a label in association with a Block. The label (referred to here as the `Key`) is stored within the `BlockAddIDExtraData` Element and the associate `Value` is stored within the corresponding BlockMore Element.
+
+### BlockAddIDType
+
+The BlockAddIDType value reserved for timecode is 107.
+
+### BlockAddIDName
+
+The BlockAddIDName value reserved for timecode is "Key Value pair".
+
+### BlockAddIDExtraData
+
+BlockAddIDExtraData stores the Key or a label for the value stored within the associated `BlockMore Element`.

block_additional_mappings_intro.md

@@ -56,3 +56,4 @@ For convenience, the following table shows the assigned BlockAddIDType values al
 | BlockAddIDType | BlockAddIDName                                               | Citation                             |
 |:---------------|:-------------------------------------------------------------|:-------------------------------------|
 | 121            | SMPTE ST 12-1 timecode                                       | (#smpte-st-12-1-timecode)            |
+| 107            | Key Value Pair                                               | (#key-value-pair)                    |