Use mesh username

src/zeronetavahi

 WEB_PAGE_TITLE=$"${PROJECT_NAME} Mesh"
 TRACKER_PORT=6969
 ZERONET_INSTALL=$MESH_INSTALL_DIR/zeronet
-MY_USERNAME=$USER
 MESH_USERNAME='fbone'
+MY_USERNAME=$MESH_USERNAME
 
 BLOGS_FILE=$ZERONET_INSTALL/${PROJECT_NAME}-blogs
 MAIL_FILE=$ZERONET_INSTALL/${PROJECT_NAME}-mail