Update command line usage text to include single letter shorthand.

src/Fixie.Console/Program.cs

@@ -178,17 +178,21 @@ static void Help()
             WriteLine("        assumed. Specify multiple project names or use * wildcards");
             WriteLine("        to run multiple test projects.");
             WriteLine();
-            WriteLine("    --configuration name");
+            WriteLine("    -c <configuration>");
+            WriteLine("    --configuration <configuration>");
             WriteLine("        The configuration under which to build. When this option");
             WriteLine("        is omitted, the default configuration is `Debug`.");
             WriteLine();
+            WriteLine("    -n");
             WriteLine("    --no-build");
             WriteLine("        Skip building the test project prior to running it.");
             WriteLine();
-            WriteLine("    --framework name");
+            WriteLine("    -f <framework>");
+            WriteLine("    --framework <framework>");
             WriteLine("        Only run test assemblies targeting a specific framework.");
             WriteLine();
-            WriteLine("    --report path");
+            WriteLine("    -r <path>");
+            WriteLine("    --report <path>");
             WriteLine("        Write test results to the specified path, using the");
             WriteLine("        xUnit XML format.");
             WriteLine();