patch 8.0.1445: cannot act on edits in the command line

Problem:    Cannot act on edits in the command line.
Solution:   Add the CmdlineChanged autocommand event. (xtal8, closes #2603,
            closes #2524)
diff --git a/runtime/doc/autocmd.txt b/runtime/doc/autocmd.txt
index 173892c..4adf007 100644
--- a/runtime/doc/autocmd.txt
+++ b/runtime/doc/autocmd.txt
@@ -1,4 +1,4 @@
-*autocmd.txt*   For Vim version 8.0.  Last change: 2017 Dec 17
+*autocmd.txt*   For Vim version 8.0.  Last change: 2018 Jan 31
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -500,6 +500,13 @@
 				command is defined.  An alternative is to
 				always define the user command and have it
 				invoke an autoloaded function.  See |autoload|.
+							*CmdlineChanged*
+CmdlineChanged			After a change was made to the text inside
+				command line.  Be careful not to mess up the
+				command line, it may cause Vim to lock up.
+				<afile> is set to a single character,
+				indicating the type of command-line.
+				|cmdwin-char|
 							*CmdlineEnter*
 CmdlineEnter			After moving the cursor to the command line,
 				where the user can type a command or search