feat: change pages with ctrl-tab

[sfoster1]

Use the common browser interaction ctrl-tab to switch pages forward and shift-tab to switch pages back.

Implementation-wise, we have to break a little layering by using the displayPages list of guids that really only the tab bar is supposed to care about... but we have to call ChangePage in the main screen, so I'm not sure how else to do it.

The other change of note is forcing a focus change when you switch tabs; this is to get any active dropdowns (i.e. the GoodsIcon dropdowns for switching recipes or switching modules) to disappear if you hit control-tab while one is open, since the mouse isn't otherwise moving and clicking like it would be if you switched tabs with the mouse.

It's also a pretty good way to test #198 by just holding down the button! This branch has both. That got merged and I rebased so you can just test that on a build of this branch

[veger]

PR looks good to me now!
I didn't test anything (only looked at code) though. So @shpaass might want to test before merging?

[veger]

wasn't removing the pane from the display pages list

Oh... When you close a page it is not deleted, so I doubt removing from the list is a good thing...
I can take a (better) look tomorrow (quite late here already), or maybe someone else can (double) check

[sfoster1]

wasn't removing the pane from the display pages list

Oh... When you close a page it is not deleted, so I doubt removing from the list is a good thing... I can take a (better) look tomorrow (quite late here already), or maybe someone else can (double) check

Yeah, I think I might be wording this improperly, but I preserved the difference between closing a page (via the X icon on the page tab in the tab bar) and deleting a page (via the "delete this page" button in the page settings dropdown). Here's a series of screenshots describing the behavior, all are from this PR:

Beginning state: several project tabs

I close the "coke hot air" page by clicking the X in the tab bar tab (screen.ClosePage()), and it's still present in the all-pages dropdown. Internally, at this point the page is

• Present in Project.pages
• Present in Project.pagesByGuid
• Not present in Project.displayPages - Project.displayPages
  
  I can click on the deemphasized text in the extra page list and it comes back. If I then delete the page from the page settings:
  
  It no longer shows up in the pages list because it's marked for deletion:
  
• It's no longer present in Project.pages
• It's no longer present in Project.pagesByGuid
  Up til now, everything is the same as master.
  In master, in this state, this page is still present in Project.displayPages, so Project.displayPages might actually be longer than project.pages, and definitely would contain content that project.pages does not. In this PR, the guid is removed from Project.displayPages.

However, I can still hit ctrl-z and it will come back and be switchable, including via shift-ctrl-tab:

[veger]

Thanks for your extended explanation, this is indeed the intended behavior.