[ANNOUNCE] git-assembler initial release

Hi everyone, I'm announcing the first "stable" release of git-assembler.

git-assembler can perform automatic merge and rebase operations
following a simple declarative script. Like "make", but for branches.

I've been using it to manage complex PRs when dealing with slow or
unresponsive upstreams and to perform testing along with with CI.

It takes inspiration from topgit, which I've also been using prior to
writing this, so if you're familiar with topgit you might also find
git-assembler useful.

Several examples along with formatted documentation are available at:

  https://www.thregr.org/~wavexx/software/git-assembler/

The source:

  https://gitlab.com/wavexx/git-assembler

Enjoy