patch 7.4.1770
Problem:    Cannot use true color in the terminal.
Solution:   Add the 'guicolors' option. (Nikolai Pavlov)
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 80d2360..8310a68 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1,4 +1,4 @@
-*options.txt*	For Vim version 7.4.  Last change: 2016 Apr 20
+*options.txt*	For Vim version 7.4.  Last change: 2016 Apr 21
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -3477,6 +3477,18 @@
 	This option cannot be set from a |modeline| or in the |sandbox|, for
 	security reasons.
 
+						*'guicolors'* *'gcol'*
+'guicolors' 'gcol'	boolean (default off)
+			global
+			{not in Vi}
+			{not available when compiled without the 
+			|+termtruecolor| feature}
+	When on, uses |highlight-guifg| and |highlight-guibg| attributes in 
+	the terminal (thus using 24-bit color). Requires a ISO-8613-3
+	compatible terminal.
+	If setting this option does not work (produces a colorless UI) 
+	reading |xterm-true-color| might help.
+
 			*'guicursor'* *'gcr'* *E545* *E546* *E548* *E549*
 'guicursor' 'gcr'	string	(default "n-v-c:block-Cursor/lCursor,
 					ve:ver35-Cursor,