Replace Just the Docs with MkDocs (#13)

* Replace Just-the-Docs with MkDocs

* Document the library

* Use default system fonts instead of imposing Roboto

* Change styling of keywords, comments, docstrings

* Integrate notebooks in documentation

* Move examples and templates from Deepnote/ to docs/

* Make external links open in new tabs

* Add configuration rationale

Deepnote/algoesup.py

@@ -20,10 +20,11 @@
 def test(function: Callable, test_table: list) -> None:
     """Test the function with the test_table. Report failed tests.
 
-    Preconditions: each element of test_table is a list or tuple with
-        - a string (the test case name)
-        - one or more values (the inputs to the function)
-        - the expected output value
+    **Preconditions**: each element of test_table is a list or tuple with
+
+    - a string (the test case name)
+    - one or more values (the inputs to the function)
+    - the expected output value
     """
     print(f"Testing {function.__name__}:")
     for test_case in test_table:
@@ -234,7 +235,7 @@ def show_ruff_json(checker: str, output: str, filename: str) -> None:
             msg = error["message"]
             if error["fix"]:
                 msg += f". Suggested fix: {error['fix']['message']}"
-            md.append(f"- {line}: \[[{code}]({url})\] {msg}")
+            md.append(rf"- {line}: \[[{code}]({url})\] {msg}")
         display_markdown("\n".join(md), raw=True)
 
 
@@ -249,7 +250,7 @@ def show_pytype_errors(checker: str, output: str, filename: str) -> None:
             msg = m.group(2)
             code = m.group(3)
             md.append(
-                f"- {line}:{msg}\[[{code}](https://google.github.io/pytype/errors.html#{code})\]"
+                rf"- {line}:{msg}\[[{code}](https://google.github.io/pytype/errors.html#{code})\]"
             )
     if len(md) > 1:
         display_markdown("\n".join(md), raw=True)

README.md

@@ -33,13 +33,10 @@ python3.10 -m venv venv
 pip install --upgrade pip
 pip install -r requirements.txt
 ```
-To preview locally the documentation that will be in GitHub Pages, follow
-[this guidance](https://docs.github.com/en/pages/setting-up-a-github-pages-site-with-jekyll/testing-your-github-pages-site-locally-with-jekyll).
-The Jekyll installation instructions include how to install Ruby.
-Bundler is usually automatically installed during the Ruby installation.
+To preview locally the documentation that will be in GitHub Pages, enter `mkdocs serve`.
 
-GitHub recommends to regularly do `bundle update github-pages` to ensure that
-the local site preview looks like on GitHub Pages.
+The documentation must be written in strict Markdown: 
+blank line before a new list; break lines with two spaces; indent with 4 spaces.
 
 After accepting a commit to folder `Deepnote/`, the owners will upload the
 updated files to the Deepnote project linked above.