Improve and modernize docs. (#2882)

* Add proper home landing page.

* Improve landing page considerably.

* Add navbar library name.

* Fix css rules.

* Update getting started images.

* Change favicon to the navbar's logo.

* Tiny change to docs index.

* Add title to home landing page.

* Tweak build overrides faq page.

* Fix FAQ article titles and headers.

* Fix FAQ article titles and headers.

* Replace channel 9 with the official .net course.

docs/faq/basics/basic-operations.md

@@ -1,6 +1,6 @@
 ---
 uid: FAQ.Basics.BasicOp
-title: Questions about Basic Operations
+title: Basic Operations Questions
 ---
 
 # Basic Operations Questions

docs/faq/basics/client-basics.md

@@ -1,6 +1,6 @@
 ---
 uid: FAQ.Basics.ClientBasics
-title: Basic Questions about Client
+title: Client Basics Questions
 ---
 
 # Client Basics Questions

docs/faq/basics/dependency-injection.md

@@ -1,9 +1,9 @@
 ---
 uid: FAQ.Basics.DI
-title: Questions about Dependency Injection.
+title: Questions about Dependency Injection
 ---
 
-# Dependency-injection-related Questions
+# Dependency Injection-related Questions
 
 In the following section, you will find common questions and answers
 to utilizing dependency injection with @Discord.Commands and @Discord.Interactions, as well as

docs/faq/basics/getting-started.md

@@ -1,15 +1,15 @@
 ---
 uid: FAQ.Basics.GetStarted
-title: Beginner Questions / How to Get Started
+title: Getting Started
 ---
 
-# Basic Concepts / Getting Started
+# Getting Started
 
 In this following section, you will find commonly asked questions and
 answers about how to get started with Discord.Net, as well as basic
 introduction to the Discord API ecosystem.
 
-## How do I add my bot to my server/guild?
+## How do I add my bot to my guild?
 
 Inviting your bot can be done by using the OAuth2 url generator provided by the [Discord Developer Portal].
 
@@ -86,10 +86,10 @@ it will return the user ID of the aforementioned user.
 > Right-clicking on the role and copying the ID will **not** work.
 > This will only copy the message ID.
 
-Several common ways to do this:
+There are several common ways to do this:
 
-1. (Easiest) Right click on the role either in the Server Settings
-   or in the user's role list.
+1. Right click on the role either in the Server Settings
+   or in the user's role list (recommended).  
    ![Roles](images/role-copy.png)
 2. Make the role mentionable and mention the role, and escape it
   using the `\` character in front.