Blender Git Loki

2.5 Buttons - Insert/Delete Keyframe Menu Tweaks

* Added 'Replace Keyframes' entry that appears in addition to delete, since it is often useful to be able to directly replace values instead of having to delete and reinsert keyframes. Internally, this just calls the Insert Keyframe operator.

* Separated the code to for Driver editing from the tests for keyframes, since they're independent.

* Added separators between keyframe and driver operations. This could be removed if the UI-mafia consider it overkill.