Add LICENSE.txt.
Install percona db with galera stuff.
Get Percona GPG keys from percona.com instead of keys.gnupg.org

gnupg.org seems to be frequently unavailable.
Fix incorrect wget '-o' flag.
Use precise release when adding percona apt-sources.

The ubuntu release is hardcoded for now, but should be configurable.
Update envs/localhost.json to work in a cloud vm with the latest code.
Further improvements to localhost.json test env.