Re #9006. Add a brief documentation field to Property.

This is by default set when the full documentation field is set and will
consist of the text up to the first period, or the entire text if no
period. An setter method is also provided to override this.
Re #9006. Use short property description in GUI tooltips.
Re #9006. Put back the full stop in the case where text is added.
Re #9006. Update a few property descriptions.
Re #9006. Update test following property description changes.
Merge remote-tracking branch 'origin/feature/9006_short_algproperty_description'