Use a dynamic method to print events to stdout

Add a flexible helper function print_event() and use it whenever we
print events to stdout. This reduces the number of copy-pasted code and
eventually allows for specifying custom format strings.

Following format specifiers are supported:

* m: Print the description of the item
* n: Print the name of the note file belonging to the item

Signed-off-by: Lukas Fleischer <calcurse@cryptocrack.de>

src/utils.c

@@ -1002,3 +1002,34 @@ print_apoint (const char *format, long day, struct apoint *apt)
         putchar (*p);
     }
 }
+
+/* Print a formatted event to stdout. */
+void
+print_event (const char *format, long day, struct event *ev)
+{
+  const char *p;
+
+  for (p = format; *p; p++)
+    {
+      if (*p == '%') {
+        p++;
+        switch (*p)
+          {
+          case 'm':
+            printf ("%s", ev->mesg);
+            break;
+          case 'n':
+            printf ("%s", ev->note);
+            break;
+          case '\0':
+            return;
+            break;
+          default:
+            putchar ('?');
+            break;
+          }
+        }
+      else
+        putchar (*p);
+    }
+}