Update README.md (#1)

Author: noahsmartin

README.md

@@ -1,3 +1,30 @@
 # ETDistribution 🛰️
 
-Keep internal builds up to date with ETDistribution
+Keep internal builds up to date with ETDistribution
+
+# Features
+
+Check for updates and automatically prompt with an option to ignore or install
+```swift
+import ETDistribution
+
+Button("Check for updates") {
+  ETDistribution.shared.checkForUpdate(apiKey: "YOUR_API_KEY")
+}
+```
+
+Or handle the update yourself
+
+```swift
+import ETDistribution
+
+ETDistribution.shared.checkForUpdate(apiKey: "YOUR_API_KEY", tagName: "alpha") { result in
+  if let update = try? result.get(), let url = ETDistribution.shared.buildUrlForInstall(update.downloadUrl) {
+    UIApplication.shared.open(url)
+  }
+}
+```
+
+# Installation
+
+Install ETDistribution with SPM using the URL of this repository (https://github.com/EmergeTools/ETDistribution)