master: restore _extract_name_from_greeting and fix its tests.

The function was removed to simplify in
575a3529425ba36592581644d651a5b24be9a50a but it was used by the tests.
This restores the function and updates the tests for the slightly
changed semantics.
node: use Net::Domain::hostfqdn instead of Sys::Hostname::hostname to get the hostname.

This actually makes the test work correctly, but might change the
returned values for some hosts.
build: no longer ignore the result of tests.

All the tests have been fixed to pass, so there is no good reason to
ignore the results.
node: always use the Effective UID not just the UID.
rrdcached is undef by default, not ""
do not use maxint
test: use the syntax that Steve used for ARRAYREFs.

Instead of declaring a temporary variable to store and get the ref of,
just use [] to get an ARRAYREF.
Merge pull request #50 from Flameeyes/restore-tests

Restore tests