Fix segfaults on 32bit arch with --log-level=debug

There were a few improper uses of %ld for 64 bit numbers, as well as
some other 32 bit related warnings that I've fixed.

Signed-off-by: ktprograms <ktprograms@gmail.com>

src/common.h

@@ -245,7 +245,7 @@ typedef struct session {
 	/// Pre-generated alpha pictures.
 	xcb_render_picture_t *alpha_picts;
 	/// Time of last fading. In milliseconds.
-	long fade_time;
+	long long fade_time;
 	/// Head pointer of the error ignore linked list.
 	ignore_t *ignore_head;
 	/// Pointer to the <code>next</code> member of tail element of the error