Merge pull request vnpy#2777 from vnpy/dev

[Mod] import from QtWidgets instead of QtGui

Merge pull request vnpy#2710 from vnpy/dev

[Mod] update version number

Merge pull request vnpy#2672 from vnpy/dev

Dev

Merge pull request vnpy#2627 from vnpy/dev

Dev

Merge pull request vnpy#2552 from vnpy/dev

[Mod] add PyQt5/pyqtgraph version number

Merge pull request vnpy#2497 from vnpy/dev

Dev

Merge pull request vnpy#2432 from vnpy/dev

Dev

Merge pull request vnpy#2384 from vnpy/dev

Dev

Merge pull request vnpy#2332 from vnpy/dev

Dev

Merge pull request vnpy#2256 from vnpy/dev

v2.0.9