Implement /console0 websocket

This commit ipmlements the serial console websocket in a way that is
compatible with phosphor-rest.  This allows the webui serial console to
function.  Latency doesn't appear improved, but I suspect that the
obmc-console server has issues.

Tested By:
Booted phosphor-webui serial console.  Serial console works as
expected.  Also implemented a serial console in python using python
websocket, and it appears to send and receive data correctly.

Change-Id: I0e571beb70a51923d6d7d148779a1154432c45c9
Signed-off-by: Ed Tanous <ed.tanous@intel.com>
diff --git a/CMakeLists.txt b/CMakeLists.txt
index dd70f94..97b3aad 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -10,6 +10,7 @@
 option (BMCWEB_ENABLE_KVM "Enable KVM websocket interfaces" ON)
 option (BMCWEB_ENABLE_DBUS_REST "Enable rest dbus interfaces" ON)
 option (BMCWEB_ENABLE_REDFISH "Enable redfish interfaces" ON)
+option (BMCWEB_ENABLE_HOST_SERIAL_WEBSOCKET "Enable host serial websocket" ON)
 option (BMCWEB_ENABLE_STATIC_HOSTING "Enable hosting of static files.
        For example, redfish schema and webui files" ON)