We want to move the tutorials that are in SVN to git version control,
preserving their histories.  This, in particular, means that the one big
edu repository needs to be moved.  Also, we need to replace the
svn:externals mechanism for latex-votut with something that works for
git.

Here's the steps MD proposes:

(1) Export svn to a local git repo

Pick a directory from https://svn.ari.uni-heidelberg.de/svn/edu/trunk/
(we won't move adqlcourse, latex-votut, py4sci and pyvo).  That's a
string like gavo_addpms.  Whatever I say gavo_addpms below, replace that
string.  Then run:

$ move-to-git/git-from-svn gavo_addpms

If this stops because:

  Author: <whatever> not defined in move-to-git/authors.txt file

ask MD to complement the authors.txt file and remove the gavo_addpms
directory.


(2) Make the text build with git

$ cd gavo_addpms
$ git log  # does the history look all right?

Fix the makefile so things will build:

$ cd en
$ sensible-editor Makefile

Put::

  ../latex-votut/Makefile:
	  cd ..; git clone https://codeberg.org/ivoa-edu/latex-votut.git

(important: the indentation *must* be a Tab character, not just space)
below the ``include ../latex-votut/Makefile``

Then run::

  make

As a side effect, this will pull the files from latex-votut.

te
Set up ignore rules:

$ cd ..
$ cp latex-votut/svn-ignore.txt .gitignore
$ git add .gitignore
$ git commit -am "Migration to git"

These step are of course not necessary when the tutorial does not use
latex-votut.


*If* you do some changes to the text, do not forget to update the
Version metadata in the README.

(3) Push to codeberg

On codeberg's web interface, do "+" -> "new repository", and choose
IVOA Edu as owner.  Put in gavo_addpms and a one sentence description of
what it is (check PDF in case of doubt).

You will end up on a page that says "Clone this repository".  Well,
don't, but copy the clone URL and say the equivalent of:

$ git remote add origin ssh://git@codeberg.org/ivoa-edu/latex-votut.git
$ git push -u origin main

To make pull requests pretty on the history and convenient all
around, go to Settings -> Units -> Pull requests, set

* "Rebase then create merge commit" as "Default merge style", and
*  check "Allow edits from maintainers by default".


(4) Create a tombstone in the SVN

Just so there are not two versions around that people will edit, check
out the original repo, empty it and say where everything has gone:

$ cd ~/tmp
$ svn checkout https://svn.ari.uni-heidelberg.de/svn/edu/trunk/gavo_addpms/
$ cd gavo_addpms
$ svn rm en res LICENSE
$ sensible-editor README

Replace the content of README with something like:

  The material that used to be here is now at
  https://codeberg.org/ivoa-edu/gavo_addpms

Finally:

$ svn commit -m "Setting a tombstone for development in svn"


(5) Update the registry record

In an svn checkout of

https://svn.ari.uni-heidelberg.de/svn/gavo/hdinputs/tutreg

edit the registry record:

$ sensible-editor gavo_addpms.rd

Locate a line with sourceURL; this should be the URL into our SVN.
Replace that URL with the http URL you just put into the README:

	sourceURL: https://codeberg.org/ivoa-edu/gavo_addpms

Then commit:

$ svn commit -m "tutreg: Updating VCS URL of gavo_addpms"