Enabled CoAP over TCP in RI Layer.

Enabled CoAP over TCP in RI Layer.

- added new transport adapter in RI
- linux platform can be supported
- https://wiki.iotivity.org/proposal_for_cloud_interface_in_iotivity

Change-Id: Iaf245c3bbf30e76708545d136435a371b86fda7e
Signed-off-by: hyuna0213.jo <hyuna0213.jo@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/2405
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: jihwan seo <jihwan.seo@samsung.com>
Reviewed-by: Jaehong Jo <jaehong.jo@samsung.com>
Reviewed-by: Patrick Lankswert <patrick.lankswert@intel.com>