Add support for GraphQL (#2947)

* Add GraphQL to languages.yml

* Add graphql submodule

* Add graphql to grammars.yml

* Add GraphQL samples

* Updating licensed information

lib/linguist/languages.yml

@@ -1262,6 +1262,14 @@ Graph Modeling Language:
   tm_scope: none
   ace_mode: text
 
+GraphQL:
+  type: data
+  extensions:
+    - .graphql
+  color: "#E535AB"
+  tm_scope: source.graphql
+  ace_mode: text
+
 Graphviz (DOT):
   type: data
   tm_scope: source.dot