VS does not close while analysis is running
description
If a long analysis is running in VS and the user closes, it will freeze until the analysis can be cancelled. Because cancellation is currently only possible between project entries, this may take a long time if the analysis is running on a large module (for example, wxPython).
We should make the cancellation more aggressive or more finely grained, and possibly take the opportunity to switch to CancellationTokens throughout.