Move functions into graphic engine layers. Cairo and Skia have their own header files and C/C++ files. Some functions are refactoried and move into graphic engine layer to make reset of MadButterfly independently from graphic engines.

#ifndef _APP_H
#define _APP_H
typedef struct {
	mb_animated_menu_t *m;
}MyAppData;

extern void MyApp_InitContent(mbaf_t *app,int argc, char *argv[]);

void myselect_callback(mb_animated_menu_t *m, int select);
#endif