Replace http:// with https:// where applicable

The testcases will be updated automatically in a separate commit.

include/ewmh.h

@@ -92,9 +92,9 @@ void ewmh_setup_hints(void);
 /**
  * i3 currently does not support _NET_WORKAREA, because it does not correspond
  * to i3’s concept of workspaces. See also:
- * http://bugs.i3wm.org/539
- * http://bugs.i3wm.org/301
- * http://bugs.i3wm.org/1038
+ * https://bugs.i3wm.org/539
+ * https://bugs.i3wm.org/301
+ * https://bugs.i3wm.org/1038
  *
  * We need to actively delete this property because some display managers (e.g.
  * LightDM) set it.

include/libi3.h

@@ -470,7 +470,7 @@ char *get_process_filename(const char *prefix);
 /**
  * This function returns the absolute path to the executable it is running in.
  *
- * The implementation follows http://stackoverflow.com/a/933996/712014
+ * The implementation follows https://stackoverflow.com/a/933996/712014
  *
  * Returned value must be freed by the caller.
  */

include/randr.h

@@ -5,7 +5,7 @@
  * © 2009 Michael Stapelberg and contributors (see also: LICENSE)
  *
  * For more information on RandR, please see the X.org RandR specification at
- * http://cgit.freedesktop.org/xorg/proto/randrproto/tree/randrproto.txt
+ * https://cgit.freedesktop.org/xorg/proto/randrproto/tree/randrproto.txt
  * (take your time to read it completely, it answers all questions).
  *
  */

include/sd-daemon.h

@@ -57,8 +57,8 @@ extern "C" {
 
   You may find an up-to-date version of these source files online:
 
-  http://cgit.freedesktop.org/systemd/plain/src/sd-daemon.h
-  http://cgit.freedesktop.org/systemd/plain/src/sd-daemon.c
+  https://cgit.freedesktop.org/systemd/plain/src/sd-daemon.h
+  https://cgit.freedesktop.org/systemd/plain/src/sd-daemon.c
 
   This should compile on non-Linux systems, too, but with the
   exception of the sd_is_xxx() calls all functions will become NOPs.