fw: basic forwarding procedure & strategy skeleton

refs #1131 #1136

Change-Id: I3e97cb17bf85082b6499a310120409379f8eaa65
core: Scheduler::cancelEvent allows empty EventId

refs #1176

Change-Id: I80f10ed8026d64b46b4634ced9278f145f54c4a7
fw: integrate forwarder, strategy, tables

refs #1131, #1136

Change-Id: Ica58341cdc1ea1dc421693a87f35fc50177a707d
face: Fixing a small bug

Change-Id: I02d6e5de2046a9cf4c9ab00a309609dfa26f6dfb
core: Logger extension to allow in-class-defined logger

Change-Id: Ifa31fb65eda772df47a81ad5db1c501eaa5f8ca1
face/tcp: Fixing TcpChannel and TcpFace implementation and enable basic logging in both

Change-Id: If9a00c13caccbeb117204655ced293d49860d6e4
refs: #1134, #1133
face: TCP end-to-end test case

The test case uses an additional Scheduler-based guard to protect
against potential communication failures.

Change-Id: I46b906f4882bfcc717b8d4a3bf074b494a39cf8d
refs: #1173
face/tcp: Fixing multiple accept on a channel

Also, this commit includes more thorough test for TCP channel (testing
if multiple connections can be made to the same channel).

Change-Id: I3b89a6d994b5b17286448013aa04a77c92c0267a
refs: #1134