docs(commands): improve and simplify commands descriptions

git commit

```

Commit the contents of the staging area with a sign-off (signature):

Commit the contents of the staging area with a sign-off signature:

```bash

git commit -s

git commit -A

```

Amend the previous commit with the current staging area content and modify the message:

Amend current commit with staged changes and modify the message:

```bash

git commit --amend

```

Amend the previous commit with the current staging area content and without modifying the message:

Amend current commit with staged changes without message edition:

```bash

git commit --amend --no-edit

  <h2>Stash</h2>

</center>

Stash the changes made in the working directory and reset to HEAD:

Stash the changes made to sources and reset to HEAD:

```bash

git stash

```

Manually stash changes chunks made in the working directory:

Manually stash changes chunks made to sources:

```bash

git stash -p

</ul>

<br />

Restore the last stashed set of changes to the working directory:

Restore the last stash of changes to the working directory:

```bash

git stash pop