Blender Git Loki

Fix T54302 - Wrong added scene when adding a scene strip to the Sequencer

When adding scene strips to the sequencer, the wrong scenes were
getting getting added if some were skipped. For example:
Given 4 scenes (A, B, C, D) if you're trying to add the last 3 scenes
(B, C, D) as strips to the first scene (A), it would ended up adding
"A, B, C" instead of "B, C, D" as expected.

Fix provided by Andrew (signal9).