Docs for SecretKit (#306)

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Sources/Packages/Sources/SecretKit/OpenSSH/OpenSSHReader.swift

@@ -1,13 +1,18 @@
 import Foundation
 
+/// Reads OpenSSH protocol data.
 public class OpenSSHReader {
 
     var remaining: Data
 
+    /// Initialize the reader with an OpenSSH data payload.
+    /// - Parameter data: The data to read.
     public init(data: Data) {
         remaining = Data(data)
     }
 
+    /// Reads the next chunk of data from the playload.
+    /// - Returns: The next chunk of data.
     public func readNextChunk() -> Data {
         let lengthRange = 0..<(UInt32.bitWidth/8)
         let lengthChunk = remaining[lengthRange]