(API Change) Un-squish obs_sceneitem_*

Renamed:                         To:
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obs_sceneitem_getscene           obs_sceneitem_get_scene
obs_sceneitem_getsource          obs_sceneitem_get_source
obs_sceneitem_setpos             obs_sceneitem_set_pos
obs_sceneitem_setrot             obs_sceneitem_set_rot
obs_sceneitem_setscale           obs_sceneitem_set_scale
obs_sceneitem_setalignment       obs_sceneitem_set_alignment
obs_sceneitem_setorder           obs_sceneitem_set_order
obs_sceneitem_getpos             obs_sceneitem_get_pos
obs_sceneitem_getrot             obs_sceneitem_get_rot
obs_sceneitem_getscale           obs_sceneitem_get_scale
obs_sceneitem_getalignment       obs_sceneitem_get_alignment