#208 has added (partially) IPLS Support.

The IPLS frame will no longer be detected as UnknownFrame but as TextInformationFrame.
Unfortunately, this does not fully work and don't return all available text.

To reprocude:
Add a new IPLS tag to an example song, for example in a tagging program like Mp3tag use INVOLVEDPEOPLE
Add a value like this:
author:Jimmy Fallon;
save it and try to read it with the help of taglib-sharp.

You only get back author as IPLS.

The expected result would be
author:Jimmy Fallon;

According to the standard:

The body simply contains a terminated string with the involvement directly followed by a terminated string with the involvee followed by a new involvement and so on.