refactor: remove qglobalshortcut

[AriaMoradi]

Closes #106

well It built successfully and I opened and tested where "combination of keys for quitting app" is and it didn't crash after a restart and pressing of the set keys.

I think if we remove the ui, we could be done.
we probably can merge and deal with bugs caused by this later!

[AriaMoradi]

now It looks like this, I did minimal deletions and just hid the element.

[AriaMoradi]

I think this is done, unless we want to hunt down the unused code...(which was already plenty beforehand!)

also after this is merged we can remove xcb from linked libraries.

[gombosg]

Thanks for setting this up! I'll take a deeper look on Friday. Let's wait 2 days for that maintainer...

[gombosg]

Can you test it like this? I removed most dead code. No bugs are caused. We can live with that 1 line left in user config .ini files.

[pktiuk]

Tested and everything works properly, but I would think about changing default size of settings window, It could be a bit smaller.

I think it looks better in this form.

[gombosg]

Yeah it's likely because of the hidden stuff in #115. But I'll try to make it smaller.

[gombosg]

Merged, thanks @AriaMoradi for setting this up.