Simplified setting the value of single-line text now that the property values received from the server are normalized.
Load multi-select lookup control asynchronously.

The application will hang when the control is loaded synchronously and the destroy command is issued for a control while it is still being loaded to the listing. This may happen if the user vigorously scrolls the property value listing up and down.
Initial support for actually changing the property values in the server.
Added LookupModel for displaying lookups in lists.
Merge branch 'master' into edit_properties_backend
Added support for editing multi-line text, integer and real property values.
Fixed invalid layout definition in SelectLookups and removed a debug message.
Support for editing Date and Time property values.
Support for editing single-select lookups.
Initial support for editing multi-select lookups.
Added missing licensing information.