Bumps RAM for app-staging under libvirt 512MB -> 1GB
Bumps RAM for app-staging under libvirt 512MB -> 1GB

This is consistent with the additional RAM allotted to VirtualBox
app-staging, and also the development VM under both providers. We simply
overlooked adding the RAM bump for the libvirt app-staging version.
While running the application tests interactively, kept running into
memory allocation errors, due to hefty Firefox and Selenium; since
bumping the RAM and rebooting, the errors have gone away.

ageis/securedrop,garrettr/securedrop,garrettr/securedrop,micahflee/securedrop,conorsch/securedrop,garrettr/securedrop,heartsucker/securedrop,heartsucker/securedrop,conorsch/securedrop,ageis/securedrop,ehartsuyker/securedrop,ehartsuyker/securedrop,heartsucker/securedrop,ehartsuyker/securedrop,ageis/securedrop,conorsch/securedrop,ehartsuyker/securedrop,conorsch/securedrop,micahflee/securedrop,heartsucker/securedrop,heartsucker/securedrop,ageis/securedrop,micahflee/securedrop,ehartsuyker/securedrop,garrettr/securedrop,micahflee/securedrop,ehartsuyker/securedrop,conorsch/securedrop