Moved CPrimaryScreen and CSecondaryScreen to the lib/synergy

and the platform specific implementations to lib/platform.
Added an lib/arch method to query the platform's native wide
character encoding and changed CUnicode to use it.  All
platform dependent code is now in lib/arch, lib/platform,
and the programs under cmd.  Also added more documentation.

cmd/synergyc/synergyc.cpp

@@ -86,6 +86,11 @@ CArgs*					CArgs::s_instance = NULL;
 // platform dependent factories
 //
 
+//! Factory for creating secondary screens
+/*!
+Objects of this type create secondary screens appropriate for the
+platform.
+*/
 class CSecondaryScreenFactory : public ISecondaryScreenFactory {
 public:
 	CSecondaryScreenFactory() { }

cmd/synergys/synergys.cpp

@@ -96,6 +96,11 @@ CArgs*					CArgs::s_instance = NULL;
 // platform dependent factories
 //
 
+//! Factory for creating primary screens
+/*!
+Objects of this type create primary screens appropriate for the
+platform.
+*/
 class CPrimaryScreenFactory : public IPrimaryScreenFactory {
 public:
 	CPrimaryScreenFactory() { }