Improve performance of the getting the CPU name and OSVersion in RayGunEnvironmentMessage

The current code queries 40+ processor variables, when we only need one
- the processor Name.  This can be very slow on some older machines(i.e.
Windows Server 2003) due to WMI calculating the LoadPercentage property.

http://stackoverflow.com/questions/5465653/wmi-loadpercentage-call-is-very-slow

Making a change to only query the properties we need, the processor name
and the os version.