Dev Docs: Add Glossary Entries & Search Links

This adds the data used to populate the glossary and search terms.

Closes #593

_data/glossary/en/consensus.yaml

@@ -0,0 +1,27 @@
+---
+# This file is licensed under the MIT License (MIT) available on
+# http://opensource.org/licenses/MIT.
+
+required:
+                                           #-------------40 characters-------------#
+    title_max_40_characters_no_formatting: Consensus
+
+    summary_max_255_characters_no_formatting: >
+        When several nodes (usually most nodes on the network) all have
+        the same blocks in their locally-validated best block chain.
+
+    synonyms_shown_in_glossary_capitalize_first_letter:
+        - Consensus
+
+optional:
+    synonyms_and_pluralizations_not_shown_in_glossary:
+        - block chain consensus
+
+    not_to_be_confused_with_capitalize_first_letter:
+        - Social consensus (often used in discussion among developers to indicate that most people agree with a particular plan)
+        - Consensus rules (the rules that allow nodes to maintain consensus)
+
+    links_html_or_markdown_style_capitalize_first_letter:
+        - "[Consensus](/en/developer-guide#term-consensus) --- Bitcoin.org Developer Guide"
+
+---