chore(docs): add Netlify docs builds

Signed-off-by: Eliza Weisman <eliza@buoyant.io>

netlify.toml

@@ -0,0 +1,11 @@
+[build]
+  command = """
+    rustup install nightly --profile minimal \
+        && cargo doc --no-deps --all-features \
+    """
+  environment = { RUSTDOCFLAGS= "--cfg docsrs -D warnings" }
+  publish = "target/doc"
+
+[[redirects]]
+  from = "/"
+  to = "/thingbuf"