Write host and PowerShell versions to log file

This change adds helpful log messages to identify the version of both the
host and the PowerShell runtime on the local machine.

Author: daviwil

src/PowerShellEditorServices.Host/Program.cs

@@ -94,7 +94,15 @@ static void Main(string[] args)
             }
 #endif
 
-            Logger.Write(LogLevel.Normal, "PowerShell Editor Services Host starting...");
+            FileVersionInfo fileVersionInfo =
+                FileVersionInfo.GetVersionInfo(
+                    System.Reflection.Assembly.GetExecutingAssembly().Location);
+
+            Logger.Write(
+                LogLevel.Normal,
+                string.Format(
+                    "PowerShell Editor Services Host v{0} starting...",
+                    fileVersionInfo.FileVersion));
 
             // Start the server
             server.Start();

src/PowerShellEditorServices/Session/PowerShellContext.cs

@@ -130,7 +130,15 @@ private void Initialize(Runspace initialRunspace)
             // TODO: Should this be configurable?
             this.SetExecutionPolicy(ExecutionPolicy.RemoteSigned);
 
-            PowerShellVersion = GetPowerShellVersion();
+            // Get the PowerShell runtime version
+            this.PowerShellVersion = GetPowerShellVersion();
+
+            // Write out the PowerShell version for tracking purposes
+            Logger.Write(
+                LogLevel.Normal,
+                string.Format(
+                    "PowerShell runtime version: {0}",
+                    this.PowerShellVersion));
 
 #if !PowerShellv3
             if (PowerShellVersion > new Version(3,0))