Rewriting settings handling - work in progress

- Created context property class for OwnKeepassSettings which will handle loading and saving of app related settings.
- Created RecentDatabaseListModel which will be used as model for SilicaListView on main page showing the recently opened databases.
Updated QML code to use the new context properties instead of the keepassSettings QML object.
Version in About page read from settings now
Recent Database list is now updated if a database is opened - work in progress
Updated layout of About page
Updated InfoPopup to match look of system notifications
Finished the user interface for loading databases

- Fixed a bug in text fields loosing focus when th eye icon was clicked
- Added dropbox location to creating and opening a database
- Added functionality to "Open automatically" button on the password query page, now the last used database will be opened by default. Setting can be unselected in password query page.
- Recent list of databases is now saved in settings. Up to 5 recent databases are now available in the list on main page
- Settings are now not stored any more in a local storage (sqlite DB) but by means of QSettings in a ini file. The settings handling code was moved to C++ side which cleans up the QML code enourmously :)