Current implementation of cgconfig.conf parser stores parameter values in

Current implementation of cgconfig.conf parser stores parameter values in
ugly string (name-value pairs separated by ':', name and value themselves
separated by ' '), which does not allow users to have ' ' and ':' in
parameter values. Both are desired for devices.allow and devices.deny.

Let's rewrite the parser to store the parsed name-value pairs in a
dictionary, without any limitation on characters allowed in names and
values.

Signed-off-by: Jan Safranek <jsafrane@redhat.com>
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>