v.edit: Add credits for extend tools (#446)

vector/v.edit/main.c

@@ -7,6 +7,7 @@
  * AUTHOR(S):  Wolf Bergenheim
  *             Jachym Cepicky
  *             Major updates by Martin Landa <landa.martin gmail.com>
+ *             Extend tools by Huidae Cho <grass4u gmail.com>
  *
  * COPYRIGHT:  (C) 2006-2017 by the GRASS Development Team
  *

vector/v.edit/v.edit.html

@@ -449,7 +449,8 @@ v.edit a2 tool=zbulk bbox=586121.25049368,4911970.21547109,603092.60466035,49270
 
 Original author: Wolf Bergenheim - independent developer<br>
 Initial updates: Jachym Cepicky, Mendel University of Agriculture and Forestry in Brno, Czech Republic<br>
-Major update by Martin Landa, FBK-irst (formerly ITC-irst), Trento, Italy
+Major update by Martin Landa, FBK-irst (formerly ITC-irst), Trento, Italy<br>
+Extend tools by Huidae Cho
 
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