[Chromoting] Add a Linux command-line app that can register and start a host.

remoting/remoting.gyp

Index: remoting/remoting.gyp
diff --git a/remoting/remoting.gyp b/remoting/remoting.gyp
index df6c2b03644b5879295a3f55ec395854bf846862..6f634146e97e140d49789313338ba7916d769c25 100644
--- a/remoting/remoting.gyp
+++ b/remoting/remoting.gyp
@@ -1153,6 +1153,17 @@
     },  # end of target 'remoting_host_plugin'
 
     {
+      'target_name': 'remoting_start_host',
+      'type': 'executable',
+      'dependencies': [
+        'remoting_host_setup_base',
+      ],
+      'sources': [
+        'host/setup/start_host.cc',
+      ],
+    },  # end of target 'remoting_start_host'
+
+    {
       'target_name': 'remoting_webapp',
       'type': 'none',
       'dependencies': [