feat: update install description (#33)

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## [SDK-744](https://ready-player-me.atlassian.net/browse/SDK-744)

## Description

- Update description for installation, that the package is no longer
installed automatically

## Changes

#### Updated

-   Updated readme





[SDK-744]:
https://ready-player-me.atlassian.net/browse/SDK-744?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

Co-authored-by: Raigo Kõvask <[email protected]>

HOW_TO_INSTALL.md

@@ -0,0 +1,40 @@
+# Quick Start
+
+### Requirements
+- Unity Version 2020.3 or higher
+- [Git](https://git-scm.com) needs to be installed to fetch the Unity package. [Download here](https://git-scm.com/downloads)
+
+**1.** To add the new Ready Player Me Unity Webview to your project you can use the Unity Package Manager to import the package directly from the Git URL.
+
+**2.** With your Unity Project open, open up the Package Manager window by going to `Window > Package Manager`.
+
+![open-package-manager](https://user-images.githubusercontent.com/7085672/206432665-da233187-06ad-40b5-a25e-660c97d6726f.png)
+
+**3.** In the **Package Manager** window click on the + icon in the top left corner and select Add Package From Git URL.
+
+![add-package-from-ur;](https://user-images.githubusercontent.com/7085672/206432698-8ecde741-4259-486f-9c77-d63fbc9a6cde.png)
+
+**4.** Paste in this url
+
+`https://github.com/readyplayerme/rpm-unity-sdk-webview.git`
+
+![paste-git-url](https://user-images.githubusercontent.com/7085672/206432731-f9e0d161-7843-4d6e-8851-47b1f3bfb3bc.png)
+
+**5.** Click add and wait for the import process to finish.
+
+After the process is complete you project will have imported these packages:
+
+- **Ready Player Me WebView**
+
+![image](https://github.com/readyplayerme/rpm-unity-sdk-webview/assets/107070960/0bb85ced-2b32-462e-bdee-b53a84f31a9d)
+
+## Alternate Installation
+
+### Using Git URL
+
+1. Navigate to your project's Packages folder and open the manifest.json file.
+2. Add this line below the `"dependencies": {` line
+    - ```json title="Packages/manifest.json"
+      "com.readyplayerme.core": "https://github.com/readyplayerme/rpm-unity-sdk-webview.git",
+      ```
+3. UPM should now install the package.

README.md

@@ -14,9 +14,10 @@ Please visit the online documentation and join our public `discord` community.
 
 ## How to install
 
-The WebView module is managed and installed automatically with the [Unity Core](https://github.com/readyplayerme/Unity-Core) module.
+Ready Player me Webview module requires, that you have core package installed.
 Please refer to the **[Quick Start guide]( https://github.com/readyplayerme/Unity-Core#readme )** for instructions on how to install the Unity Core module.
 
+The installation steps for the Webview module can be found **[here.](HOW_TO_INSTALL.md)**
 
 Users can create Ready Player Me avatars seamlessly in a WebView displayed within a Unity application.
 
@@ -109,4 +110,4 @@ As such the following classes are now located in the Ready Player Me Core module
 - WebViewEvents
 
 If you have any scripts in your Unity project that reference these classes you will need to update the namespace to use ReadyPlayerMe.Core instead of ReadyPlayerMe.WebView, be sure to update the import statements in these scripts.
-EG: `using ReadyPlayerMe.WebView;` should be changed to `using ReadyPlayerMe.Core;`
+EG: `using ReadyPlayerMe.WebView;` should be changed to `using ReadyPlayerMe.Core;`