New Features

- Added an option to sort saving goals based on different conditions inside settings menu.
- Bunch of UI improvements, redesigned dialogs for filter goals menu, backup & restore menu, and currency setup dialog shown at first launch.
- Made deadline optional parameter, also added new additional notes field which can be used to store some extra information related to saving goals.

Improvements & Fixes

- Improvements in Spanish translations, thanks to Sergio Varela.
- Fixed edit goal page popping in backstack after editing existing saving goal.
- Bunch of performance optimizations here and there.
- Refactored project structure and organised files accordingly.