SDL segment properties re-written with Container-level values

[YvesS]

When reading a <target> with several segments, we store the SDL segments properties in two places:

• In the TextContainer (because we didn't have properties at the segment level initially). And if there are several segments, the values are of that last segment.
• In each Segment (when we added the properties at the segment-level)

The problem is that when re-writing the modifiable properties (like origin), we use the values of the TC-level properties rather than each segment's own. So, we end up with the properties for the last segment for all segments.

Issue is in updateSdlSeg() and possibly having the same placeholder ID for all segments skeleton parts.

[YvesS]

This is fixed with https://bitbucket.org/okapiframework/okapi/commits/730b937a548f1240fefff35e4febbf43e6ecaf76