Expand export options i.e. what information shall be included

[ludsinn]

As discussed, it would be nice to offer the user what information he/she wants to include in a file.
For instance, instead of having to join columns informatically from different files, it would be nice to have all information one needs in just one file right after exporting.

Example: I want to compare the cross-links content fractionwise between two experiments (and also check for redundancy). The proposal is to add categorical columns to the "links"-file with the raw-file name as header for facile filtering.