Make revision history linear

[snomos]

Presently the revision history is as follows:

I would like the highlighted merge to be deleted, and the parent commits be ordered sequencially and chronologically.

Reason: I have a recollection that a linear revision history is an implicit requirement of gut template apply, and the delta algorithm. If I am mistaken, and it has no bearing, please just close.

We are experiencing four repos that are not template mergable (ie nothing happens), and suspect that this might be related/the reason.

[snomos]

If rewriting history creates new sha's (which it most likely will), the sha of all language repos (.gut/delta.toml) has to be updated correspondingly, so that the correct sha is found when doing the next template merge.

[snomos]

Fixed in the latest commits.

NB! Did force-push, so make sure to pull before editing further.