Wikipedia: add showRedirects option for toggling redirect output

Sometimes showing redirects adds a lot of clutter to an already cramped snippet space, making text a lot harder to read. This adds a configuration option to turn redirect showing on or off.

Before:

```
<+GLolol> `wiki Widnows
<@Atlas> I didn't find anything for "Widnows". Did you mean "windows"? "Microsoft Windows" (Redirected from "Windows"): Microsoft Windows or Windows is a metafamily of graphical operating systems developed, marketed, and sold by Microsoft. It consists of several families of operating systems, each of which cater to a certain sector of the computing industry. Active Windows families include Windows NT, (1 more message)
```

After (with showRedirects off):

```
<+GLolol> `wiki Widnows
<@Atlas> Microsoft Windows or Windows is a metafamily of graphical operating systems developed, marketed, and sold by Microsoft. It consists of several families of operating systems, each of which cater to a certain sector of the computing industry. Active Windows families include Windows NT, Windows Embedded and Windows Phone; these may encompass subfamilies, e.g. Windows Embedded Compact (Windows CE) or (1 more message)
```