build-image.sh is now taking parameters: -i -g

build-image.sh is now taking parameters: -i -g

The -i option is now specifying the appendix for the the image name. The
name of the image will be rapid-<appendix>.qcow2. The -i option could then
be used to specify 'latest' or 'stable'.
The -g option specifies the google storage url where the qcow2 will be
stored.
The -v option is still existing in case we want to only verify the qcow2
image creation process.
An example:
buils-image.sh -g artifacts.opnfv.org/samplevnf/images -i latest -v

Change-Id: Ie07a89eff029f4e9fd3e1f2ebff1eaea05c580a6
Signed-off-by: Luc Provoost <luc.provoost@intel.com>