The fixes introduced in order to resolve
https://bugs.launchpad.net/nova/+bug/1409142 (CVE-2015-0259) make
novncproxy_base_url relevant on hosts running the nova-novncproxy
service, whereas previously it was only used by nova-compute to
construct VNC console urls.
This change moves the setting of the novncproxy_base_url option out of
compute.pp and into nova::vncproxy_common, where it can be used both
by compute.pp and vncproxy.pp.
Change-Id: I7af4cf8257f2bdbc7d3cc57930fd6371571db531
28268ad9c7