Implement support for SCTE-35 switching messages.

This module implements a dissector for the main table in a SCTE-35 message, a
splice_info_section. This payload is carried in a MPEG Section Table with a
table ID of 0xFC. PIDs carrying this sort of table are also noted in the PMT
with a stream type of 0x86, and a registration descriptor with fourcc 'CUEI'.

The various splice command types are implemented in separate modules, and are
linked to this dissector through the field scte35.splice_command_type. Field
names follow the conventions documented in the SCTE35 specification.

This dissector does not support encrypted SCTE35 messages, other than
indication through the scte35.encrypted_packet flag.

The SCTE-35 protocol is described by the Society of Cable Telecommunications
Engineers at <https://www.scte.org/documents/pdf/Standards/Top%20Ten/ANSI_SCTE%2035%202013.pdf>.

Bug: 12521
Change-Id: I3113e6e61a4e7f1a4a932a0128ca2846c7ce6e6f
Reviewed-on: https://code.wireshark.org/review/15562
Petri-Dish: Michael Mann <mmann78@netscape.net>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Anders Broman <a.broman58@gmail.com>

AUTHORS.src

@@ -3674,6 +3674,9 @@ Barbu Paul - Gheorghe	<barbu.paul.gheorghe[AT]gmail.com> {
 Martin Kacer	<kacer.martin[AT]gmail.com> {
 	JSON and Elasticsearch tshark output
 }
+Ben Stewart		<bst[AT]google.com> {
+	SCTE-35 dissector
+}
 
 Sumit Kumar Jha		<sjha3[AT]ncsu.edu> {
 	Generic Protocol Extension Support for VXLAN

docbook/release-notes.asciidoc

@@ -128,6 +128,8 @@ vSocket
 ISO 15765
 Unified Diagnostic Services (UDS)
 Encrypted UDP based FTP with multicast
+SCTE-35 Digital Program Insertion Messages
+
 --sort-and-group--
 
 === Updated Protocol Support

epan/dissectors/CMakeLists.txt

@@ -1161,6 +1161,7 @@ set(DISSECTOR_SRC
 	packet-scsi-smc.c
 	packet-scsi-ssc.c
 	packet-scsi.c
+	packet-scte35.c
 	packet-sctp.c
 	packet-sdh.c
 	packet-sdlc.c

epan/dissectors/packet-mpeg-pmt.c

@@ -109,6 +109,7 @@ static const value_string mpeg_pmt_stream_type_vals[] = {
     { 0x24, "ITU-T Rec. H.265 and ISO/IEC 23008-2 (Ultra HD video) in a packetized stream" },
     { 0x7F, "IPMP stream" },
     { 0x81, "ATSC A/52 Audio" },
+    { 0x86, "SCTE-35 Splice Information" },
     { 0xA1, "ETV-AM BIF Data Stream" },
     { 0xC0, "ETV-AM EISS Signaling" },
     { 0x00, NULL }