finagle: Update scrooge-sbt-plugin version to 4.7.0

Problem

The scrooge-sbt-plugin version should be updated to 4.7.0 for release

Solution

Update the version.

RB_ID=826940
TBR=true

Bump versions - util/ostrich/finagle/scrooge/twitter-server

Prepare libraries for release.

RB_ID=809587

release: Prepare libraries for OSS release

RB_ID=796660

csl: Release OSS libraries

Finagle 6.31
Util 6.30
Scrooge 4.2
TwitterServer 1.16
Ostrich 9.14

RB_ID=774633
TBR=true

csl: bump lib versions

RB_ID=756082
TBR=true

Release CSL libraries (Sept 2015).

- Release finagle, ostrich, scrooge, twitter-server, util (Sept 2015).

RB_ID=747942

Release CSL stack

RB_ID=735615

Release CSL Stack

RB_ID=721327

release CSL OSS

release new minor version of all CSL OSS.

twitter-server: 1.11.0
scrooge: 3.19.0
finagle-*: 6.26.0
ostrich: 9.9.0
util: 6.25.0

RB_ID=701418
TBR=true

csl: Publish externally with pants, sbt, and friends

Problem

It's difficult to publish util, finagle, etc. because we haven't
updated them for the new maven-less world.

Solution

Scripts that make it easy to publish with sbt and pants.  Bumped
the server-set version because we stopped publishing thrift
externally in ci.  Changed an ExitGuard test which broke under
weird sbt conditions.

Result

We're in a position where we can start publishing finagle, etc
again!

RB_ID=633570