Feat: Add a scroll bar in space list and improve UX for space selection

[PhilippeAccorsi]

At present

This is not easy to understand that a big list of space can be synchronise. We can use the mouse wheel

Also, if I click on a name, the space is directly added, and if i move with keyboard, all space are added. Same to remove space.

Expected

• have a scroll bar in each column and/or
• use something like that to add/remove space (with button to add/remove all space

[buxx]

Config window is difficult to tweak because TKinter technology. Maybe direct go to the https://github.com/buxx/trsync/issues/45

[PhilippeAccorsi]

Ok.

[buxx]

UI updated in last version