Support horizontal stack views and minor bug fixes

• Added support for horizontal AloeStackViews, via the axis property.
• Fixed an additional issue with touches not being passed to UIControls in rows when a tap handler is set.

Thank you to @neobeppe and @apptekstudios for contributing to this release, and everyone else that has supported AloeStackView!

Minor bug fixes

• Fixed an issue where UIControls inside rows would not receive touch events if a tap handler was set.
• Improved cell highlighting behavior so rows unhighlight if a user drags their finger outside a row without lifting up.
• Bumped the Swift version of the CocoaPod to 5.0.

Huge thanks to the contributors for this release: @colinhumber and everyone else that has contributed to AloeStackView!

Support Swift 5.0

• Support for Swift 5.0
• Support for Package Manager in Xcode 11
• Support for automatically flashing a scroll indicator
• Support for retrieving first and last row of the stack view
• Added support for custom cell highlights
• Bug fixes and improvements

Huge thanks to all of the contributors for this release:
@Dschee, @kaunamohammed, @florianldt, @tadija, @alexbredy, @yanamura, Colin Reisterer, @fonkadelic, @marlimox, and everyone else that has contributed to AloeStackView!

Support both Swift 4.0 and 4.2

We added CI support to ensure the project builds with both Swift 4.0 and 4.2