Add Server-Sent-Event support

Server-Sent-Event is a standard describing how servers can initiate
data transmission towards clients once an initial client connection has
been established. Unlike websockets (which are bidirectional),
Server-Sent-Events(SSE) are unidirectional and commonly used to send
message updates or continuous data streams to a browser client.

This is base patch for adding Server-Sent-Events routing support to
bmcweb. Redfish EventService SSE style subscription uses SSE route for
sending the Events/MetricReports to client which establishes the
connection.

Tested this patch with along with EventService SSE support patches and
verified the functionalty on browser.

Tested:
 - Tested using follow-up patches on top which adds
   support for Redfish EventService SSE style subscription
   and observed events are getting sent periodically.
 - Created SSE subscription from the browser by visiting
   https://<BMC IP>/redfish/v1/EventService/SSE

Change-Id: I36956565cbba30c2007852c9471f477f6d1736e9
Signed-off-by: AppaRao Puli <apparao.puli@linux.intel.com>
Signed-off-by: P Dheeraj Srujan Kumar <p.dheeraj.srujan.kumar@intel.com>
Signed-off-by: V-Sanjana <sanjana.v@intel.com>

0 files changed, 0 insertions, 0 deletions