[CMake] CMake 2.6.3 - Fix set cache FORCE and -D command line to work together

[Bill Hoffman]

Andreas Schneider wrote:
> Hi,
> 
> what means
> 
> 	- Fix set cache FORCE and -D command line to work together
> 
> I've recognized, that -DFOO=something doesn't overwrite cache settings anymore 
> which are set to FORCE. Is this true?
> 
> If yes, then the documentation should be updated. -D states:
> 
> 	This option may be used to specify a setting that takes priority over the
> 	project's default value.
> 

Force is not a default value, force is force.

-Bill