updated the manual for the new WRITE block

was #2448 thanks, @brianharvey

HISTORY.md

@@ -6,10 +6,12 @@
 * **Notable Changes:**
 * **Notable Fixes:**
     * fixed a layout glitch for variadic C-shaped input slots, thanks, Bernat, for reporting it!
+    * updated the manual for the new WRITE block, thanks, Brian
 * **Translation Updates:**
 
 ### 2019-07-09
 * blocks: fixed a layout glitch for variadic C-shaped input slots, thanks, Bernat, for reporting it!
+* updated the manual for the new WRITE block, thanks, Brian (was #2448)
 
 ### 2019-07-08
 * new dev version