Herald v2 (#74)

* Add speech rate setting

* Add volume slider

* New speech manager skeleton

* User API key from resx

* Implement voice list retrieve via new api

* Rewrite to use ObAPI, remove all dependancies

* Use volume setting

* Clean up using statements

* Volume and timing adjustments

* Lookup rate value

* Use numeric rates for tighter spread

* Manage plugin data folder via core interface

* Add check that nullable settings are not null.

* Get file size before it's deleted.

* Improve old settings migration.

* Ignore cache sizes below 1MB

* Re-index orphaned files in cache, purge legacy wav files.

* Call top level error logging for native voice exception.

* Async title and detail requests to remove pause

* Remove NetCoreAudio use of temp files.

* Remove orphan using.

ObservatoryHerald/NetCoreAudio/Player.cs

@@ -0,0 +1,98 @@
+using NetCoreAudio.Interfaces;
+using NetCoreAudio.Players;
+using System;
+using System.Runtime.InteropServices;
+using System.Threading.Tasks;
+
+namespace NetCoreAudio
+{
+    public class Player : IPlayer
+    {
+        private readonly IPlayer _internalPlayer;
+
+        /// <summary>
+        /// Internally, sets Playing flag to false. Additional handlers can be attached to it to handle any custom logic.
+        /// </summary>
+        public event EventHandler PlaybackFinished;
+
+        /// <summary>
+        /// Indicates that the audio is currently playing.
+        /// </summary>
+        public bool Playing => _internalPlayer.Playing;
+
+        /// <summary>
+        /// Indicates that the audio playback is currently paused.
+        /// </summary>
+        public bool Paused => _internalPlayer.Paused;
+
+        public Player()
+        {
+            if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+                _internalPlayer = new WindowsPlayer();
+            else if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
+                _internalPlayer = new LinuxPlayer();
+            else if (RuntimeInformation.IsOSPlatform(OSPlatform.OSX))
+                _internalPlayer = new MacPlayer();
+            else
+                throw new Exception("No implementation exist for the current OS");
+
+            _internalPlayer.PlaybackFinished += OnPlaybackFinished;
+        }
+
+        /// <summary>
+        /// Will stop any current playback and will start playing the specified audio file. The fileName parameter can be an absolute path or a path relative to the directory where the library is located. Sets Playing flag to true. Sets Paused flag to false.
+        /// </summary>
+        /// <param name="fileName"></param>
+        /// <returns></returns>
+        public async Task Play(string fileName)
+        {
+            await _internalPlayer.Play(fileName);
+        }
+
+        /// <summary>
+        /// Pauses any ongong playback. Sets Paused flag to true. Doesn't modify Playing flag.
+        /// </summary>
+        /// <returns></returns>
+        public async Task Pause()
+        {
+            await _internalPlayer.Pause();
+        }
+
+        /// <summary>
+        /// Resumes any paused playback. Sets Paused flag to false. Doesn't modify Playing flag.
+        /// </summary>
+        /// <returns></returns>
+        public async Task Resume()
+        {
+            await _internalPlayer.Resume();
+        }
+
+        /// <summary>
+        /// Stops any current playback and clears the buffer. Sets Playing and Paused flags to false.
+        /// </summary>
+        /// <returns></returns>
+        public async Task Stop()
+        {
+            await _internalPlayer.Stop();
+        }
+
+        private void OnPlaybackFinished(object sender, EventArgs e)
+        {
+            PlaybackFinished?.Invoke(this, e);
+        }
+
+        /// <summary>
+        /// Sets the playing volume as percent
+        /// </summary>
+        /// <returns></returns>
+        public async Task SetVolume(byte percent)
+        {
+            await _internalPlayer.SetVolume(percent);
+        }
+
+        public void Dispose()
+        {
+            _internalPlayer.Dispose();
+        }
+    }
+}