webos.inc: Restrict CONNECTIVITY_CHECK_URIS and add Ubuntu-14.04 to tested distros

* use only http://jenkins.nas-admin.org (where we run PR service) and
  http://build.webos-ports.org where we have sstate mirror, some yocto
  URLs used before sometimes take longer to respond and the sanity check
  timeouts and fails

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>