all: bump dep on mellium.im/xmlstream to v0.13.3
xmpp: tweak docs about SendElement and IQs
jid: add more tests
xmpp: don't mask Dialer's DNS resolver
xmpp: clarify fallback order for dial

See #2
xmpp: make SendElement safe for concurrent use
roster: fix nil pointer access
roster: only call underlying close method once
roster: add roster fetching and async parsing
xmpp: fix bug where stream might get out of sync
xmpp: minor update to Send example in docs
xmpp: add tests for sending stanzas
xmpp: extract out long is IQ and is stanza checks
xmpp: update docs that mention the issue tracker
xmpp: clarify error message in example test
examples: add expanded echobot example
xmpp: fix detection of non-IQ start elements
all: allow negotiating received sessions
.builds: don't fail on linting issues
.builds: use correct build tree name