journal: render markdown content + title metadata

this has a really basic template and whatnot at the moment, so
styling/etc isn't done, but this is maybe the last major piece before I
could actually see pushing this onto the site

requirements/requirements.txt

@@ -8,5 +8,9 @@ click==7.0                # via flask
 flask==1.1.1              # via -r requirements/requirements.in
 itsdangerous==1.1.0       # via flask
 jinja2==2.11.1            # via flask
+markdown==3.2.1           # via -r requirements/requirements.in
 markupsafe==1.1.1         # via jinja2
 werkzeug==1.0.0           # via flask
+
+# The following packages are considered to be unsafe in a requirements file:
+# setuptools