Some parameters (like devices.allow) shall include a space in their values.

Some parameters (like devices.allow) shall include a space in their values.
This patch adds possibility to specify parameters names in double quotes,
like:
	devices {
		devices.allow="c 1:3 mr";
	}

The double quotes are not mandatory, old  behavior is still there.

As side effect, also parameter names, group names, user names, controller names
etc. can be (optionally) in double quotes and can contain weird characters
- it's a feature, not a bug :). Of course, I could change the grammar to allow
double quotes only in param. values, that shouldn't be a problem.

There is also no advance handling of escape sequences - \", \n, \t does not work
here. That means that parameter values cannot contain newline or double quote
characters - are they required by any controllers?

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