Rename "awesome" to "AwesomeWM"; update image, links

Based on examining the AwesomeWM project's web presences and Wikipedia
entry, there does not appear to be a single consistent name by which the
project refers to its window manager. All three of these variations are
used: "awesome", "Awesome", and "AwesomeWM". In order to avoid ambiguity
with the regular English word, we're opting for "AwesomeWM" in our own
documentation.

This commit also reverts the change to the widget image, since that
change was not necessary (see #1161).

Finally, this commit adds links to the KDE, i3, and AwesomeWM pages.

user/how-to-guides/how-to-get-started.md

@@ -95,8 +95,8 @@ all the same color --- or all different colors. It's entirely up to you.
 On operating systems like Windows and macOS, the desktop environment is
 unchangeable and part of that operating system. With Linux, any of a number of
 desktop environments are an option. Qubes OS is installed with XFCE as its
-default desktop environment, but it also supports KDE, as well as the i3 and
-Awesome window managers.
+default desktop environment, but it also supports [KDE](/doc/kde/), as well as
+the window managers [i3](/doc/i3/) and [AwesomeWM](/doc/awesomewm/).
 
 [![r4.0-taskbar.png](/attachment/doc/r4.0-taskbar.png)](/attachment/doc/r4.0-taskbar.png)
 
@@ -125,9 +125,11 @@ There are several Tray widgets that are unique to Qubes OS:
  - The **Qubes Disk Space Monitor** will notify you if you're ever running out
    of disk space.
  - The **Qubes Update** tool will inform you when updates are available.
- - The **Whonix SDWDate** widget surfaces and tracks functionality unique to the [Whonix project's integration with Qubes OS](https://www.whonix.org/wiki/Qubes).
+ - The **Whonix SDWDate** widget surfaces and tracks functionality unique to
+   the [Whonix project's integration with Qubes
+   OS](https://www.whonix.org/wiki/Qubes).
 
-![QubesWidgets_2](https://user-images.githubusercontent.com/8262612/122690403-3cec5c00-d1de-11eb-8abf-f954ad24b790.png)
+[![r4.0-widgets.png](/attachment/doc/r4.0-widgets.png)](/attachment/doc/r4.0-widgets.png)
 
 To see all of your qubes at the same time, you can use the **Qube Manager** (go
 to the App Menu → System Tools → Qube Manager), which displays the states of