moved misc helper functions to separate file and removed redundant includes

src/commands.c

@@ -8,10 +8,9 @@
 
 #include <stdlib.h>
 #include <string.h>
-#include <ctype.h>
 
 #include "toxic_windows.h"
-#include "prompt.h"
+#include "misc_tools.h"
 #include "commands.h"
 
 extern char *DATA_FILE;
@@ -513,4 +512,4 @@ void execute(WINDOW *window, ToxWindow *prompt, Tox *m, char *u_cmd, int buf_len
     /* no match */
     free(cmdargs);
     wprintw(window, "Invalid command.\n");
-}
+}