docs: Fix more capitalization issues.

Signed-off-by: Anders Kaseorg <anders@zulip.com>

docs/tutorials/life-of-a-request.md

@@ -16,7 +16,7 @@ application will serve the request (or deciding to serve the request
 itself for static content).
 
 In development, `tools/run-dev.py` fills the role of nginx. Static files
-are in your git checkout under `static`, and are served unminified.
+are in your Git checkout under `static`, and are served unminified.
 
 ## Static files are [served directly][served-directly] by Nginx
 
@@ -167,7 +167,7 @@ its url patterns (see
 [zerver/lib/rest.py](https://github.com/zulip/zulip/blob/master/zerver/lib/rest.py))
 so that the action called is `rest_dispatch`. This method will
 authenticate the user, either through a session token from a cookie,
-or from an `email:api-key` string given via HTTP Basic Auth for API
+or from an `email:api-key` string given via HTTP basic auth for API
 clients.
 
 It will then look up what HTTP verb was used (GET, POST, etc) to make

docs/tutorials/new-feature-tutorial.md

@@ -147,7 +147,7 @@ document it and update any existing documentation that might be
 relevant to the new feature. For more information on the kinds of
 documentation Zulip has, see [Documentation](../documentation/overview.md).
 
-## Example Feature
+## Example feature
 
 This example describes the process of adding a new setting to Zulip: a
 flag that allows an admin to require topics on stream messages (the default

docs/tutorials/writing-views.md

@@ -112,7 +112,7 @@ which is documented in detail at
 [zerver/lib/rest.py](https://github.com/zulip/zulip/blob/master/zerver/lib/rest.py).
 This method will authenticate the user either through a session token
 from a cookie on the browser, or from a base64 encoded `email:api-key`
-string given via HTTP Basic Auth for API clients.
+string given via HTTP basic auth for API clients.
 
 ``` py
 >>> import requests