add new steps to transition lessons to Workbench

{% assign date = include.need_transition_date %}

{% unless site.transition_url %}

<div class="alert alert-danger">

  you need to specify the variable <code>transition_url</code>

  in <code>_config.yml</code>.

</div>

{% endunless %}

{% if date == "true" %}

{% unless site.transition_date %}

<div class="alert alert-danger">

  you need to specify the variable <code>transition_date</code>

  in <code>_config.yml</code>.

</div>

{% endunless %}

{% endif %}

	{% endif %}

    </div>

    <div class="col-md-6 help-links" align="right">

	{% if page.source %}

	{% if page.source == "Rmd" %}

        {% if site.life_cycle contains 'transition_step' %}

        <a href="{{repo_url}}">Edit on GitHub</a>

        {% elsif page.source == "Rmd" %}

	<a href="{{repo_url}}/edit/{{ default_branch }}/{{page.path|replace: "_episodes", "_episodes_rmd" | replace: ".md", ".Rmd"}}" data-checker-ignore>Edit on GitHub</a>

	{% endif %}

	{% else %}

	<a href="{{repo_url}}/edit/{{ default_branch }}/{{page.path}}" data-checker-ignore>Edit on GitHub</a>

	{% endif %}

{% elsif site.life_cycle == "stable" %}

{% comment %}

We do not do anything special unless this is a Carpentries Lab lesson

We do not do anything special for lessons in stable

{% endcomment %}

{% comment %}

Below we cover the 3 phases of lesson transition towards the Carpentries Workbench:

- transition_step_1 (`transition_url` variable needed): we indicate that there

is a new version of the lesson that is available for testing, and that it will be deprecated in the future.

- transition_step_2 (`transition_url` and `transition_date` variables needed): we indicate that a new version of the lesson is avaiable with a deprecation date.

- transition_step_3 (`transition_url` variable needed): the lesson if fully deprecated, and a redirect is set up to the new URL

{% endcomment %}

{% elsif site.life_cycle == "transition_step_1" %}

{% include check_transition_variables.html need_transition_date = 'false' %}

<div class="alert alert-warning life-cycle">

  A newer version of this lesson is being tested:

  <a href="{{ site.transition_url }}">{{ site.transition_url }}</a>.

  This lesson will become deprecated in the near future.

</div>

{% elsif site.life_cycle == "transition_step_2" %}

{% include check_transition_variables.html need_transition_date = 'true' %}

<div class="alert alert-danger life-cycle">

  A newer version of this lesson is available from: <a href="{{ site.transition_url }}">{{ site.transition_url }}</a>.

  This lesson will become deprecated on {{ site.transition_date }}.

</div>

{% elsif site.life_cycle == "transition_step_3" %}

{% include check_transition_variables.html need_transition_date = 'false' %}

<div class="alert alert-danger life-cycle">

    This lesson is deprecated. A newer version is available from: <a href="{{ site.transition_url }}">{{ site.transition_url }}</a>.

</div>

{% endif %}

{% comment %}

For Carpentries Lab lessons we add a banner about the review status

{% endcomment %}

{% if site.carpentry == "lab" %}

  </div>

</div>

{% endif %}

{% endif %}

	{% comment %} Always show license. {% endcomment %}

        <li><a href="{{ relative_root_path }}{% link LICENSE.md %}">License</a></li>

	{% if page.source %}

	{% if page.source == "Rmd" %}

        {% if site.life_cycle contains 'transition_step' %}

        <li><a href="{{repo_url}}">Improve this page <span class="glyphicon glyphicon-pencil" aria-hidden="true"></span></a></li>

        {% elsif page.source == "Rmd" %}

	<li><a href="{{repo_url}}/edit/{{ default_branch }}/{{page.path|replace: "_episodes", "_episodes_rmd" | replace: ".md", ".Rmd"}}" data-checker-ignore>Improve this page <span class="glyphicon glyphicon-pencil" aria-hidden="true"></span></a></li>

	{% endif %}

	{% else %}

	<li><a href="{{repo_url}}/edit/{{ default_branch }}/{{page.path}}" data-checker-ignore>Improve this page <span class="glyphicon glyphicon-pencil" aria-hidden="true"></span></a></li>

	{% endif %}

    {% include favicons.html %}

    {% if site.life_cycle == 'transition_step_3' %}

    <meta http-equiv="refresh" content="0; url={{ site.transition_url }}" />

    {% endif %}

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