Optimize assets

• Fix theme version
• Update contact info

Use SVG icons

• Use SVG dropdown arrow
• Fix qmldir component versions
• Update license identifier
• Code cleanup

Change project structure

• Fix qmldir license header
• Update install instructions

Fix drop-down lists

• Fix QML import issue with a qmldir file in the components directory
• Import components into a qualified local namespace
• Fix drop-down lists

Use GridLayout to show the login form

Hopefully this will make it easy to maintain

Remove avatarSource from theme.conf

• Remove hardcoded avatar path and use the one from userModel.icon
• Add missing KeyNavigation.backtab/KeyNavigation.tab
• Sall improvements

Update for SDDM v0.14.0

• Replace default.face.icon with .face.icon
• Remove note in README.md

Code refactoring

• Remove unneeded code
• Update Qt version dependency to 5.6 or higher
• Exclude unneeded files from tarballs

Set custom settings in theme.conf

• Allow to change background color in theme.conf
• Allow to change time and date font size in theme.conf
• Remove unneeded chunks of code
• Code refactoring

Add custom clock

• Create a custom clock to allow the user to change time and date format
• Update preview image
• Update README.md