add_idc_hotkey

Add hotkey for IDC function
     hotkey  - hotkey name ('a', "Alt-A", etc)
     idcfunc - IDC function name
returns:
#define IDCHK_OK        0       // ok
#define IDCHK_ARG       -1      // bad argument(s)
#define IDCHK_KEY       -2      // bad hotkey name
#define IDCHK_MAX       -3      // too many IDC hotkeys

long add_idc_hotkey(string hotkey, string idcfunc);