Update ChangeLog for version 0.5.0 release.
Update ChangeLog for version 0.5.0 release.

Change-Id: I914c289b3e14495a972a57f072c65e63c3801238
Signed-off-by: Christopher M. Cantalupo <9cf3ecca60a3dd7112ab0e7250bedb8a752e3958@intel.com>

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