add unsupported features table

Signed-off-by: Adam Ratzman <[email protected]>

Author: adamint

README.md

@@ -40,8 +40,6 @@ repositories {
 implementation("com.adamratzman:spotify-api-kotlin-core:3.4.01")
 ```
 
-Note that images and profiles are not supported on the Kotlin/JS target.
-
 ### Android
 **If you declare any release types not named debug or release, you may see "Could not resolve com.adamratzman:spotify-api-kotlin-android:VERSION". You need to do the following for each release type not named debug or release:**
 ```
@@ -78,6 +76,16 @@ If you have a question, you can:
 2. Join our [Discord server](https://discord.gg/G6vqP3S)
 3. Contact me using **Adam#9261** on [Discord](https://discordapp.com)
 
+## Unsupported features on each platform:
+| Feature                     | JVM                | Android            | JS                 | Native (Mac/Windows/Linux) |
+|-----------------------------|--------------------|--------------------|--------------------|----------------------------|
+| Images (Playlist covers)    | :heavy_check_mark: | :heavy_check_mark: | Unsupported        | Unsupported                |
+| getSpotifyPkceCodeChallenge | :heavy_check_mark: | :heavy_check_mark: | Unsupported        | Unsupported                |
+| Edit client playlist        | :heavy_check_mark: | :heavy_check_mark: | :heavy_check_mark: | Unsupported                |
+
+Please feel free to open an issue/discussion on GitHub or Discord if you need access to one of these features 
+or have an interest in implementing one, as direction can be provided.
+
 ## Creating a new api instance
 To decide which api you need (SpotifyAppApi, SpotifyClientApi, SpotifyImplicitGrantApi), you can refer 
 to the sections below or the [Spotify authorization guide](https://developer.spotify.com/documentation/general/guides/authorization-guide/). In general: