Switch many URLs to https://; update them if broken or redirected

SUPPORT.markdown

@@ -3,11 +3,11 @@ Mailing List
 
 For assistance on using, or customising, these scripts please consult
 the manpages initially, then the
-[website](http://xen-tools.org/software/xen-tools/).
+[website](https://xen-tools.org/software/xen-tools/).
 
 If these are not sufficient resources please consider posting any
 queries you might have to the [mailing
-list](http://xen-tools.org/software/xen-tools/lists.html)
+list](https://xen-tools.org/software/xen-tools/lists.html)
 
 Included with the release you should find the file `BUGS.markdown`
 which contains some notes on reporting bugs.
@@ -18,13 +18,13 @@ Xen Queries
 
 If your query is mostly related to Xen, rather than these tools, then
 please consider joining the [xen-users mailing
-list](http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-users)
+list](https://lists.xenproject.org/cgi-bin/mailman/listinfo/xen-users)
 
 The members of that list are very good at diagnosing issues with
 networking, block devices, and other Xen oddities.
 
 There's also the IRC channel `##xen` (the double hashmark is not a
- typo) on the [Freenode](http://freenode.net/) IRC network.
+ typo) on the [Freenode](https://freenode.net/) IRC network.
 
 
 Contact The Author