Added README and fixed publish script.

The publish script used platform specific options, and this commit removes
them. This commit introduces a README with installation instructions.

README.md

@@ -0,0 +1,35 @@
+# Dakota's tilde.club
+
+This is the repository for building Dakota's tilde.club page. As of now, the
+only build artifact is `index.html`.
+
+## Dependencies
+
+- `python3`
+  - Python packages listed in `requirements.txt`
+
+### Optional Dependencies
+
+- [tidy](https://github.com/htacg/tidy-html5/blob/next/README/BUILD.md)
+
+## Installation
+
+1.  Clone the repository and `cd` into the cloned directory.
+2.  Make a virtualenv (optional, but highly suggested) and activate it:
+
+```bash
+python -m venv .venv
+source .venv/bin/activate
+```
+
+3.  Install the `python` package dependencies using `pip`:
+
+```bash
+python -m pip install -r requirements.txt
+```
+
+4.  Run the publish script:
+
+```bash
+./publish.py
+```

publish.py

@@ -1,13 +1,17 @@
 #!/usr/bin/env python
 
 import io
-from subprocess import run
+from subprocess import run, DEVNULL
 
 import markdown
 from jinja2 import Template
 
 def main():
-    tidy_exists = run(["which", "-s", "tidy"]).returncode == 0
+    tidy_exists = run(
+        ["which", "tidy"],
+        stdout=DEVNULL,
+        stderr=DEVNULL
+    ).returncode == 0
     with open("readings.md") as readings, open("index.tmpl.html") as tmpl:
         readings_html = markdown.markdown(readings.read())
         template = Template(tmpl.read())