Play Instant Unity Plugin Versions Save

• Add support for 2019.3 (#142)
• Automated build changes

• Changes to accommodate the latest versions of 2017.4 and 2018.3
• Fix ApkSigner usage with .NET 4.5

• Added Quick Deploy feature for building an AssetBundle with the game's main scene and building a Loading scene to download that AssetBundle from a server (used to minimize size of APK)
• Added a menu item to check for and download updates to the plugin

• Add Cookie API that an instant app can use to store data for retrieval post-install #22
• Fix whitespace handling of file and scene paths #20

• Adds support for Unity 5.6 by re-signing APKs with apksigner
• Adds a "Build for Play Console" menu option that creates a ZIP file containing a single APK
• Provides additional control over scenes included in the build via the "Build Settings" menu option (formerly "Configure Instant or Installed")

This release adds a method to launch a Play Store install dialog from the instant app. See the README for details.

Initial beta release of the Google Play Instant Plugin for Unity.

See the README for installation instructions and supported features.