Changed the way loader.c loads Clock/iButton/U2F

Added a new variable in application.fam file to add the link to the FAP. It now supports any FAP as long as the application.fam file is formatted correctly and you create a loader "app".

If no link is specified in the application.fam file, it doesn't attempt to load a FAP.

applications/services/applications.h

@@ -10,10 +10,11 @@ typedef enum {
 
 typedef struct {
     const FuriThreadCallback app;
-    const char* name;
+    char* name;
     const size_t stack_size;
     const Icon* icon;
     const FlipperApplicationFlag flags;
+    char* link;
 } FlipperApplication;
 
 typedef void (*FlipperOnStartHook)(void);