doc: add NEWS section for 0.6.26
doc: add NEWS section for 0.6.26

gloryleague/avahi,Kisensum/xmDNS-avahi,Kisensum/xmDNS-avahi,catta-x/catta,gloryleague/avahi,lathiat/avahi,heftig/avahi-1,Distrotech/avahi,Kisensum/xmDNS-avahi,Distrotech/avahi,heftig/avahi,Distrotech/avahi,heftig/avahi,heftig/avahi,lathiat/avahi,heftig/avahi-1,Distrotech/avahi,catta-x/catta,gloryleague/avahi,lathiat/avahi,Distrotech/avahi,everbase/catta,heftig/avahi,everbase/catta,gloryleague/avahi,gloryleague/avahi,Kisensum/xmDNS-avahi,Kisensum/xmDNS-avahi,Kisensum/xmDNS-avahi,lathiat/avahi,lathiat/avahi,heftig/avahi-1,heftig/avahi-1,heftig/avahi,heftig/avahi-1,gloryleague/avahi,everbase/catta,catta-x/catta,heftig/avahi-1,Distrotech/avahi,lathiat/avahi,heftig/avahi