obsolete: unify collapsed revisions markers handling
When collapsing A, B and C into D, amend was registering:
A -> D
B -> D
A -> B
C -> D
A -> C
while the rebase wrapper was doing:
A -> D
B -> D
C -> D
At this point, I have no argument to favor one or another or even a new
one like:
A -> B
B -> C
C -> D
so I am aligning the rebase implementation on the older amend one. At
least we can now change them all at once.
6c6bb7a23bb5125bf06da73265f039dd3447dafa 0.1.0
d3f20770b86a31dba56ae7b252089e12b34702da 0.2.0