Merge remote-tracking branch 'killyourtv/68-multi' into david-68work

Here we adapt the multi-introducer patch (ticket #68)
to accomodate the new sequence number and nonce scheme from ticket #1767.
We pass the current_seqnum and current_nonce into IntroducerClient's publish method
instead of that publish method calling the passed in _sequencer function to generate
that sequnum/nonce pair.

Manually resolved conflicts in these files:
	src/allmydata/client.py
        src/allmydata/introducer/client.py
        src/allmydata/introducer/interfaces.py
Leaving these files to Leif's commit to be merged later:
	src/allmydata/test/test_web.py
	src/allmydata/web/root.py
	src/allmydata/web/welcome.xhtml
Merge leif/ticket68 into david-68work

Conflicts:
	src/allmydata/client.py
	src/allmydata/test/test_web.py
	src/allmydata/web/root.py
	src/allmydata/web/welcome.xhtml
Fix syntax error and do not pass sequencer function...
fix allmydata.test.test_web.Web.test_GET_root_html