Added doc about `APP_BASEPATH` (#557)
Added doc about `APP_BASEPATH` (#557)

The `APP_BASEPATH` setting can be used to specify where the higlass server should look for the admin interface.
hms-dbmi/higlass,hms-dbmi/4DN_matrix-viewer,hms-dbmi/higlass,hms-dbmi/4DN_matrix-viewer,hms-dbmi/higlass,hms-dbmi/higlass,hms-dbmi/4DN_matrix-viewer