Make catalog short title a bit larger and handle too long titles

The catalog short title introduced with 15.0 is limited to 16 characters. This fits well into the tile visualization even when the title has many wide characters. 

In practice however the short title can be up to 20 characters which does also fit in most cases. 

The goal of this issue is to extend the short title to 20 characters and deal with overflow by ellipsing it if necessary.