Fix edoc generation
Add Travis CI
Return the servers when asked to do so

Return the elarm_server children - not an empty list (as it does now),
not a list containing the elarm_registry (as a badly written patch
could do).
Add unit tests re which_servers
Merge pull request #25 from lastres/fix-edoc

Fix edoc generation
Merge pull request #26 from lastres/travis-ci

Add Travis CI
Merge pull request #27 from lucafavatella/fix-which_servers

Fix internal elarm_sup:which_servers/0 and test which_servers