Blender Git Commit Log

Sequencer: Add session UUID management to Sequence

This is the first step for having sequences covered with session UUID
with the goal to remove code which uses original sequence pointer to
match sequences.

Currently this UUID is maintained on file load, allocation and leaf
duplication function.There are more cases to cover and ensure UUID
is re-generated or re-used when needed. It will be done as follow-up
development.