Updating HAProxy snapshot documentation v1.5.1-19 generated by haproxy-dconv v0.3.1-23

b4fca5d DOC: explicitly mention the limits of abstract namespace sockets
Updating HAProxy snapshot documentation v1.6-dev0-29 generated by haproxy-dconv v0.3.1-23

70f72e0 DOC: explicitly mention the limits of abstract namespace sockets