Merge branch 'add-const-qualifiers' into doxygen-fixes

Conflicts:
	Source/cmPropertyDefinition.h

Source/cmWhileCommand.h

@@ -61,17 +61,17 @@ public:
   /**
    * This determines if the command is invoked when in script mode.
    */
-  virtual bool IsScriptable() { return true; }
+  virtual bool IsScriptable() const { return true; }
 
   /**
    * The name of the command as specified in CMakeList.txt.
    */
-  virtual const char* GetName() { return "while";}
+  virtual const char* GetName() const { return "while";}
 
   /**
    * Succinct documentation.
    */
-  virtual const char* GetTerseDocumentation() 
+  virtual const char* GetTerseDocumentation() const
     {
     return "Evaluate a group of commands while a condition is true";
     }
@@ -79,7 +79,7 @@ public:
   /**
    * More documentation.
    */
-  virtual const char* GetFullDocumentation()
+  virtual const char* GetFullDocumentation() const
     {
     return
       "  while(condition)\n"