Traceability: Support for multiple-select

The customer created a Custom Field with type Select list (Multiple choice). He can't display it in the traceability matrix.

The user will be able to select to display the values as a comma separated list, as a bullet list or as multiple cells

It includes the export as an Excel file

After 2.6.3:

• Export Excel support

• Support change display for standard fields: components, fix version, labels, affects version, description

• Fix display for the textarea on multiline