Added some information about Qt Creator IDE integration to the wiki

[Michael Weghorn]

On 26/02/2021 08.53, Michael Weghorn wrote:
> This is on Debian testing and I've checked that on Windows as well.
> Can you share your autogen.input (if present) and share your vcl.pro via 
> pastebin (or send by email)?

Now that the Jenkins CI builds have finished, I have merged the pending 
patches. It may be worth trying again with current master first, in case 
any of the changes might already have fixed the issue for your setup...