Better tabs

[dasjestyr]

Tabs should allow for

• Reordering of logs. Enable tab re-ordering which should also update the 'order' property on the log so that the order is saved between sessions.
• Docking could be useful, but there is no behavior for this in the stock control set

Dragablz is a promising alternative (https://github.com/ButchersBoy/Dragablz) but on my first attempt to integrate it, I found that there are some binding quirks that cause the application to crash due to a stack overflow (xaml binding calls property setter infinitely). I logged an issue on the Dragablz github -- hopefully there will be either a fix or workaround soon.