Repository: rasterio/rasterio

Issue:
Dead links
<!--

WELCOME ABOARD!

Hi and welcome to the Rasterio project. We appreciate bug reports, questions
about documentation, and suggestions for new features. This issue template
isn't intended to ward you off; only to intercept and redirect some particular
categories of reports, and to collect a few important facts that issue reporters
often omit.

The primary forum for questions about installation and usage of Rasterio is 
https://rasterio.groups.io/g/main. The authors and other users will answer 
questions when they have expertise to share and time to explain. Please take the
time to craft a clear question and be patient about responses. Please do not
bring these questions to Rasterio's issue tracker, which we want to reserve for
bug reports and other actionable issues.

Questions about development of Rasterio, brainstorming, requests for comment,
and not-yet-actionable proposals are welcome in the project's developers 
discussion group https://rasterio.groups.io/g/dev. Issues opened in Rasterio's
GitHub repo which haven't been socialized there may be perfunctorily closed.

Please note: Rasterio contains extension modules and is thus susceptible to
C library compatibility issues. If you are reporting an installation or module
import issue, please note that this project only accepts reports about problems
with packages downloaded from the Python Package Index. Conda users should take
issues to one of the following trackers:

- https://github.com/ContinuumIO/anaconda-issues/issues
- https://github.com/conda-forge/rasterio-feedstock

Also please note: we are currently working on 1.0 and pre-releases. Bugs found
in version 0.36 will not be fixed except in a 1.0 alpha or beta release. In 
some cases, 0.36 bugs have already been fixed in recent pre-releases.

You think you've found a bug? We believe you!
-->

While skimming through the documentation, I found a dead link (404). Following that, I used a small bash script to test all links:
```bash
grep -oIhrE "(https?:[^ >]+)[a-zA-Z/0-9]" | sort | uniq | awk '{print $1 " -o /dev/null"}' > /tmp/URL_LIST.txt
xargs curl -sw "%{url_effective}\t %{http_code}\t %{redirect_url}\\n" < /tmp/URL_LIST.txt 
```
It found just a few 404 (actually quite some, due to `example.com/...`, but that's desired), a bunch of 302 (mostly because of named anchors), quite some 301 (http -> https), and a 410. I'll create a PR to fix the obvious ones, and we can discuss here (or in the PR) if more should be fixed.


Discussion:

Resolving patch:
diff --git a/rasterio/__init__.py b/rasterio/__init__.py
--- a/rasterio/__init__.py
+++ b/rasterio/__init__.py
@@ -91,7 +91,7 @@ def open(fp, mode='r', driver=None, width=None, height=None, count=None,
     driver : str, optional
         A short format driver name (e.g. "GTiff" or "JPEG") or a list of
         such names (see GDAL docs at
-        http://www.gdal.org/formats_list.html). In 'w' or 'w+' modes
+        https://gdal.org/drivers/raster/index.html). In 'w' or 'w+' modes
         a single name is required. In 'r' or 'r+' modes the driver can
         usually be omitted. Registered drivers will be tried
         sequentially until a match is found. When multiple drivers are


Test patch: