* Fix two problems introduced in ejabberd 2.0.4: subscription request produced
many authorization requests with some clients and transports; and
subscription requests were not stored for later delivery when receiver was
offline.
* Fix warning in expat_erl.c about implicit declaration of x_fix_buff
* HTTP-Bind (BOSH): Fix a missing stream:error in the returned
remote-stream-error stanza
* Do not ask certificate for client (c2s)
* Check digest-uri in SASL digest authentication
* Use send timeout to avoid locking on gen_tcp:send
* Fix ejabberd reconnection to database
* HTTP-Bind: handle wrong order of packets
* MUC: Improved traffic regulation management
* PubSub: Several bugfixes and improvements for best coverage of XEP-0060 v1.12
* Shared Roster Groups: push immediately membership changes
* Rotate also sasl.log on "reopen-log" command
