Powershell version of "fake remote" for rebase exercises

[JKrag]

In #192 I made some general features to support "real" remotes in katas and used these in the "reorder history" kata.
I never completed the Powershell version, although I might have an unfinished version on a branch somewhere. I am not PS proficient, so I would love if someone else could make these.

I will make separate issues for implementing these changes on other katas

[JKrag]

I now found my lost branch with WIP powershell version. I don't remember exactly what state it was in, but it was not complete enough to include in #192
I have pushed the branch to improve-rebase-powershell as a starting point.

[bothzoli]

hi @JKrag i tested your branch and for me it works correctly.
do you have any issue in particular? i'd be happy to help

[JKrag]

@bothzoli There might actually not be anything missing. I can no longer remember as I did the original work about a year ago. It is quite probable that I made the equivalent changes to the PS version, but without any environment to test it (and no real experience with PS), so I just didn't feel comfortable including it in the original PR. So I might have been lucky and made a bug-free version in the first attempt. Later, I just found my branch laying around, at a time where I didn't have time to investigate, and just pushed it for someone else to look at.
If you have tested it, and both the general utils and the specific changes in the "reorder the history" kata work as intended, then we are probably happy to merge it.
Any comments on this @RandomSort ?