Merge pull request #2 from olenz/master

New theme: "Vertical"
Use "border" without using additional space
Merge branch 'master' of github.com:Emdek/plasmoid-adjustable-clock
Correct indentation
Update TODO
Initial draft of new Clock API interface
Missing files
Update copyright year
Load custom themes from shared data file
Save custom themes to shared data file
Move custom themes from old location when found
Fix condition
Watch for external themes data changes
Fix identifiers of custom themes
Less intrusive way to set default font family
Fix font family in previews
Improve look of placeholders in editor
Avoid infinite loops while converting custom themes
Fix interferences (for example timezone name) between different instances
Update changelog