Fix issue with tray icon double clicking.

When clicking the tray icon in rapid succession on
windows the next click on it wouldn't register.
Analysis showed the signal really didn't reach the
handler. It seems like there are some bad things
happening when calling activateWindow() in this
handler as when it is called this issue disappears.
As our setWindowState call should perform window
activation anyways we now simply rely on it and
remove the other call. Also unified both track
click handlers.

Fixes #1452
Transifex translation update

Mode: default
Minimum percent translated: 0
Matched 31 languages

Closes #1450
Added Windows 10 in OS detection and manifest file.

The official name for the server version of Windows 10
is "Windows 10 Server Technical Preview" but since
"Technical Preview" is a detail, I haven't included it.

Closes #1435
Revert "Fix issue with tray icon double clicking."

This reverts commit a120c8eb28c0dfcdfdb0981c63147bb37d45df2c.

Turns out this prevented Mumble from being able to raise
itself in front of a maximized application. The click
not being reported after using the activateWindow function
is probably a Qt bug and if it's reproducible in a small
sample should be reported.
Transifex translation update
Mode: default
Minimum percent translated: 0
Matched 31 languages