build: Use pkgconfig, work with naemon include guards

The include guards prevent including anything other than
naemon/naemon.h, so that's what we include.

Signed-off-by: Robin Sonefors <robin.sonefors@op5.com>
configure: Silence warnings about initialization order

We used to call lt_init, then ac_prog_libtool (which is an older name
for the same thing), and then ac_prog_ar and ac_prog_ranlib for weird
compatibility reasons.

Skip ranlib, it's supposedly useless. Put ar before the libtool
thingies, as libtool overrides them. Put only one libtool name -
lt_init is supposedly "newer", I'll just use the old one until that
starts to warn as well.

Signed-off-by: Robin Sonefors <robin.sonefors@op5.com>
make travis use testing repository

Signed-off-by: Sven Nierlein <Sven.Nierlein@consol.de>