cmCommand: remove unused methods from interface and all implementations

Source/cmConfigureFileCommand.h

@@ -25,11 +25,6 @@ public:
   bool InitialPass(std::vector<std::string> const& args,
                    cmExecutionStatus& status) CM_OVERRIDE;
 
-  /**
-   * The name of the command as specified in CMakeList.txt.
-   */
-  std::string GetName() const CM_OVERRIDE { return "configure_file"; }
-
 private:
   int ConfigureFile();