Do not use “-y” for package install
Do not use “-y” for package install

According to "code conventions" [1], do not use "-y" option.
Instead, use apt-get install package, yum install package,
or zypper install package.

[1] https://docs.openstack.org/doc-contrib-guide/writing-style/
code-conventions.html

Change-Id: I11ffc5627f32a9300a5fea0d79d334c3acf09b0f

stackforge/refstack,stackforge/refstack,openstack/refstack,openstack/refstack,stackforge/refstack,openstack/refstack,stackforge/refstack,openstack/refstack