Add labels for title/abstract inclusions

[EmilyWes]

Currently the labels in the SYNERGY dataset tell if a record is included during the full text screening.
For some research it might also be useful to have a dataset where the inclusions indicate a title/abstract inclusion.
The first 2 ways to include this information that come to mind are:

1. Alter the definition of a dataset so it can contain both the full text inclusion label as well as a title/abstract label.
2. Add an additional dataset for the title/abstract inclusions.

The first option requires some changes in the Synergy pipeline, as well as some changes which inclusion type to select for use in ASReview. It is also good to note that not all datasets have both types of labels available.

The second option would work in the current style, but would create a lot of duplicate data.