Add Graphviz dependency (for the dot program), used from Doxygen
Add Graphviz dependency (for the dot program), used from Doxygen

Ghabry/easyrpg-liblcf,EasyRPG/liblcf,EasyRPG/liblcf,carstene1ns/easyrpg-liblcf,Ghabry/easyrpg-liblcf,Zegeri/liblcf,EasyRPG/liblcf,EasyRPG/liblcf,Zegeri/liblcf,Ghabry/easyrpg-liblcf,fdelapena/easyrpg-liblcf,carstene1ns/easyrpg-liblcf,glynnc/liblcf,Zegeri/liblcf,glynnc/liblcf,fdelapena/easyrpg-liblcf,glynnc/liblcf,glynnc/liblcf,Ghabry/easyrpg-liblcf,fdelapena/easyrpg-liblcf,carstene1ns/easyrpg-liblcf