Initial structure for VCL event logging.
Initial structure for VCL event logging.

- WIP: taking a LARGE patch and breaking into smaller chunks
- large LDP/VCL refactor in progress. This minimizes rebase.
- LARGE patch removed clib_warning()s erroneously
- VPPCOM_DEBUG checks duplicated deliberately as clib_warning()
  usage will be refactored.

Change-Id: I5905ed074187fe22c9f1320fd07ffcaab3a0f63c
Signed-off-by: Keith Burns (alagalah) <469d26a9115c63bc10d4323e29088530ee1e798d@gmail.com>

chrisy/vpp,FDio/vpp,vpp-dev/vpp,chrisy/vpp,chrisy/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,vpp-dev/vpp,vpp-dev/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,vpp-dev/vpp,vpp-dev/vpp,FDio/vpp,vpp-dev/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,vpp-dev/vpp