Git: move files retaining history

git-move-dir.txt

From the source repository:
```sh
git clone <src_repository> <src_repository>_clone
# clone the src repository in new folder
```

```sh
cd <src_repository>_clone
```

```sh
git remote rm origin
# remove the origin to avoid disasters in case of error
```

```sh
git filter-branch --subdirectory-filter <directory> -- --all
# the magic, rewrite the git history
```

```sh
mkdir <directory>
mv * <directory>
# create the directory and move everything inside
```

In the destination repository:

```sh
git remote add <src_repository> <git repository A directory>
# clone clone the repository, if not previously done
```

```sh
git pull repo-A master --allow-unrelated-histories
# Import the src repository code into the dst repository
```

```sh
git mv <directory_1> <desired_position>
# Optionally, move the just imported files, into the desired position in the new repository
```

git-move.sh

#!/bin/bash

mkdir -p newroot/

# Pipe output to silence "file not found" warnings.
mv README.md newroot/ 2>/dev/null
mv src newroot/ 2>/dev/null

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