added toolbar button

[dplewinska]

issue #391

[joeraz]

The button works. However, it remains enabled if the deal cards option is not currently allowed, while the menu item is grayed out and the talon is either blocked or not present.

Also, I am not a fan of having one button with no icon. I've got the icon libraries set aside locally, and can review to add one.

[shlomif]

@dplewinska @joeraz : any update?

[joeraz]

No further updates - there are still two reasons I did not merge this PR:

• The button is always enabled, and not enabled/disabled the way the corresponding main menu item is.
• The button does not have an icon, which gives it an inconsistent UI from the remaining buttons - I could add something with the icon libraries I have myself, but would need to figure out which icon to use.