remove the broken/deprecated redirect tag support

when this project *wasn't* a SSG, it could serve up redirects, which is
something that was only rarely needed, and looking now, I don't do it at
all on any of my current sites, so I'm just going to remove the tiny bit
of code for it that remained in the SSG project

Signed-off-by: Brian S. Stephan <bss@incorporeal.org>

incorporealcms/markdown.py

@@ -135,11 +135,6 @@ def handle_markdown_file_path(path: str, pages_root: str) -> str:
     extra_footer = get_meta_str(md, 'footer') if md.Meta.get('footer') else None
     template_name = get_meta_str(md, 'template') if md.Meta.get('template') else 'base.html'
 
-    # check if this has a HTTP redirect
-    redirect_url = get_meta_str(md, 'redirect') if md.Meta.get('redirect') else None
-    if redirect_url:
-        raise NotImplementedError("redirects in markdown are unsupported!")
-
     template = jinja_env.get_template(template_name)
     return template.render(title=page_title,
                            config=Config,

tests/instance/broken/redirect.md

@@ -1 +0,0 @@
-Redirect:           http://www.google.com/

tests/test_markdown.py

@@ -103,12 +103,6 @@ def test_render_with_default_style_override():
                 in handle_markdown_file_path('index.md', PAGES_DIR)
 
 
-def test_redirects_error_unsupported():
-    """Test that we throw a warning about the barely-used Markdown redirect tag, which we can't support via SSG."""
-    with pytest.raises(NotImplementedError):
-        handle_markdown_file_path('redirect.md', os.path.join(INSTANCE_DIR, 'broken'))
-
-
 def test_instance_resource_path_to_request_path_on_index():
     """Test index.md -> /."""
     assert instance_resource_path_to_request_path('index.md') == '/'