rework event api
remove debug code.
improve docs.
move 'observable' module from conductance to sjs stdlib
update sjs
Merge branch 'master' into events-refactor

Conflicts:
	modules/sjs-lib-index.json
docs
accept a filter function for AllowCORS, supporting sharing to multiple origins
surface::Enabled() should set attribute, not class
fix defaulting of AllowCORS origins setting
travis: build only master & release branches
polymorphic event::wait
update std.sjs
Merge branch 'master' into events-refactor
minor code simplification
Fix filename logic on windows.
written tests to expose a broken connection being unnoticed
retract server side execution initiated by client on broken connection
delete old bridge-tests related to automatic reconnection
docs