Falling Keyboard

Minor release. Primary changes are:

• Use Legacy build system to fix Mojave builds (@kastiglione, #251)
• Add macOS build (@kastiglione, #247)
• Fix issue with visualize (@kastiglione, #244)
• Added pviews --window flag to show UIWindows (@PeteTheHeat, #239)
• Add support for printing json format for Swift Dictionaries and Arrays (@arorajatin, #238)
• Fixed fa11y command on iOS 10 and higher (@bartoszj, #237)