Ignore any database.yaml .
respond to MEMBER-DELETE request
add MEMBER-DELETE to the list of allowed commands
add tests for MEMBER-DELETE handler
search by username instead of member id
update libertree-model
catch connection failure and retry
Bump libertree-model-rb and m4dbi .
Bump libertree-model-rb .
Bump factory_girl and dependencies.
Introduce @forest in tests .
Unnest some inner spec contexts that should not be nested.
Bump rspec.
Added Libertree::Server#in_a_forest? .
Return "UNRECOGNIZED SERVER" code when requester is not in any forest that the local server is a member of.
It doesn't have to be specifically INTRODUCE that triggers UNRECOGNIZED SERVER.
support MEMBER-DELETE jobs
update libertree-client

Since commit d34a9f95c94705 libertree-client supports
MEMBER-DELETE requests.
Merge branch 'master' into xmpp

Conflicts:
	Gemfile.lock
	lib/libertree/server.rb
	lib/libertree/server/responder/dispatcher.rb
rewrite MEMBER-DELETE responder

- simplify checks with `assert`
- use `fail` to respond with error codes