Remove unused syslog_forwarder

We colocate the metron agent to configure syslog instead [#79811028]
Bump cacheddownloader

Bump pivotal-golang/cacheddownloader:
  Ted Young:
     use chan struct{} instead of chan interface{} for semaphores ( Travis Success: https://travis-ci.org/pivotal-golang/cacheddownloader/builds/36827482 )
     test for Content-Length verification ( Travis Unknown )
Merge remote-tracking branch 'origin/develop' into develop
Add diego deploy CI scripts which consume final release [#76625036]

Signed-off-by: Nick Wade <nwade@pivotallabs.com>
Create final release 0.446 for build 200