New feature: ability to move tabs between windows

[kjk]

Thanks to efforts of @avorobey In latest pre-release version you can:

• move tabs between window
• drag tabs within window
• drag out a tab to create a new window.

Also tweaked the display of tabs.for bigger contrast between tab and background, so it's easier to tell selected tab.

[linbdnil]

I love this feature. Current issue is it become easily crash (if not always) when using forward-search of latex (the inverse-search work well), my tool combination is vscode + latex workshop + miktex + sumatrapdf (build 15374), and the 3.4.6 version work well with both forward-search and inverse-search.

[venkat2305]

Please add dark mode too

[CalebSpencerTorch]

I tested the pre-release with this feature. It worked well until it crashed so I'm looking forward to further development of this feature.

[GitHubRulesOK]

@CalebSpencerTorch
for a crash its best to follow the guide that pops up (on cancel) and supply the details if its repeatable otherwise your cause may not be addressed, the more good quality repeatable crash submittals the better the quality of next release