feat: Add AoT compilation with webpack (#215)

Added AoT/Webpack support and updates it to NativeScript 2.5

Fixes #213

- Various bug fixes for Android, especially Android 6

- Remember the user’s sign indefinitely

- Added the ability to add groceries via history

- Added checkboxes to toggle grocery items
- A brand new look for Android from various styling improvements
- Add a pull to refresh UI for refreshing the list
- Various improvements to loading times, processing indicators, and keyboard management

- Added the ability to reset your password within the app

- Added better keyboard management
    - The app no longer lets the keyboard overlay text fields
    - The app hides the keyboard when you tap off of a text field
    - Turned off autocorrection and autocomplete for email fields

- Initial release of Groceries to the iOS App Store and Google Play