Update runtime files

runtime/doc/syntax.txt

@@ -1,4 +1,4 @@
-*syntax.txt*	For Vim version 8.2.  Last change: 2021 Jun 22
+*syntax.txt*	For Vim version 8.2.  Last change: 2021 Jul 02
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -1420,11 +1420,17 @@ To select syntax highlighting file for Euphoria, as well as for
 auto-detecting the *.e and *.E file extensions as Euphoria file type,
 add the following line to your startup file: >
 
-	:let filetype_euphoria = "euphoria3"
+	:let g:filetype_euphoria = "euphoria3"
 
 <	or >
 
-	:let filetype_euphoria = "euphoria4"
+	:let g:filetype_euphoria = "euphoria4"
+
+Elixir and Euphoria share the *.ex file extension.  If the filetype is 
+specifically set as Euphoria with the g:filetype_euphoria variable, or the
+file is determined to be Euphoria based on keywords in the file, then the
+filetype will be set as Euphoria. Otherwise, the filetype will default to
+Elixir.
 
 
 ERLANG						*erlang.vim* *ft-erlang-syntax*
@@ -1442,6 +1448,22 @@ To enable highlighting some special atoms, put this in your vimrc: >
       :let g:erlang_highlight_special_atoms = 1
 
 
+ELIXIR						*elixir.vim* *ft-elixir-syntax*
+
+Elixir is a dynamic, functional language for building scalable and maintainable
+applications.
+
+The following file extensions are auto-detected as Elixir file types:
+
+	*.ex, *.exs, *.eex, *.leex, *.lock
+
+Elixir and Euphoria share the *.ex file extension. If the filetype is 
+specifically set as Euphoria with the g:filetype_euphoria variable, or the
+file is determined to be Euphoria based on keywords in the file, then the
+filetype will be set as Euphoria. Otherwise, the filetype will default to
+Elixir.
+
+
 FLEXWIKI				*flexwiki.vim* *ft-flexwiki-syntax*
 
 FlexWiki is an ASP.NET-based wiki package available at http://www.flexwiki.com