Adds documentation to README for Ubuntu support
Adds documentation to README for Ubuntu support

- Lists packages required for Ubuntu.
- Gives example for building under Ubuntu.
- Fixes #600

Change-Id: Ic550a408e1ca8fdff3ef2fedc98e61481ba72969
Signed-off-by: Barry Rountree <03fdb2694a520bad3d3bcfcaea88575777960cce@protonmail.com>
Signed-off-by: Brad Geltz <e42f3ad4099980ea02f08e076efbee5cf9d4a803@intel.com>

geopm/geopm,geopm/geopm,geopm/geopm,geopm/geopm,cmcantalupo/geopm,geopm/geopm,cmcantalupo/geopm,cmcantalupo/geopm,cmcantalupo/geopm,cmcantalupo/geopm