Add langs/README

Author: ubolonton

README.org

@@ -0,0 +1,9 @@
+This is a convenient bundle of language grammars and queries for ~tree-sitter~. It serves as an interim distribution mechanism, until ~tree-sitter~ is widespread enough for language major modes to include these definitions on their own.
+
+Basically it's a multi-phase adoption process:
+
+1. ~tree-sitter-langs~ populates global registries of grammars and queries. These global registries are defined by ~tree-sitter-mode~ and other ~tree-sitter~-based language-agnostic minor modes, to extend existing major modes.
+
+2. New ~tree-sitter~-based language-specific minor modes use these global registries to extend existing major modes.
+
+3. Major modes adopt new ~tree-sitter~-based features, and distribute the grammars and queries on their own. They can either put these definitions in the global registries, or keep using them only internally.

tree-sitter-langs.el

@@ -16,7 +16,7 @@
 ;; `tree-sitter' is widespread enough for language major modes to include these
 ;; definitions on their own.
 ;;
-;; Basically it's a multi-step process:
+;; Basically it's a multi-phase adoption process:
 ;;
 ;; 1. `tree-sitter-langs' populates global registries of grammars and queries.
 ;;    These global registries are defined by `tree-sitter-mode' and other