First pass at implementing Jackdaw as a Plover dictionary

_dictionaries/jackdaw.md

@@ -0,0 +1,43 @@
+---
+layout: dictionary
+title: Jackdaw orthographic chords
+date: 2016-06-22
+version: 1
+filename: jackdaw
+author: Lindsay Winkler
+tags: words briefs
+what: Implement proposed Jackdaw orthographic chords
+formats:
+  - json
+---
+
+## Why
+This dictionary implements orthographic chords from the 
+[Jackdaw proposal](https://sites.google.com/site/ploverdoc/jackdaw) for use with Plover.
+
+This is a first pass at the dictionary, and is intended to enable hands on experimentation
+with what's described in the proposal, to assist in further refining it.
+
+Jackdaw intends to provide orthographic, rather than phonetic chords, and therefore
+behaves somewhat differently to a regular steno theory.  Chords are divided into onset (with
+the left hand), vowels (with the thumbs) and coda (with the right hand).  These three elements
+are combined in a deterministic way to produce the output.
+
+Because the two leftmost keys in Plover are both logically `S`, the leading `A` key in
+the Jackdaw proposal can't be implemented with a standard Plover dictionary.  That means
+none of the chords beginning with `A` are available.
+
+The proposed fourth part of the chord - the inflection - is not implemented here.
+
+Keys in Jackdaw are named and ordered differently to those on the standard steno keyboard
+that Plover works with. 
+
+This is a fairly inefficient way to implement Jackdaw: because the parts of the chord are
+combined by concatenating left to right, there's no need to have a dictionary with every possible
+key combination.  Jackdaw can be implemented directly in keyboard firmware, and fit in memory
+on a keyboard, for example.  This dictionary, though, offers the possibility for existing Plover
+users to explore the concept.
+## How
+
+Just add this dictionary to Plover's list, such that it takes precedence over
+your core Plover dictionary (`dict.json` or `main.json`).