finagle|util: Fix broken changelogs
finagle|util: Fix broken changelogs

- Dublicated section "Runtime Behavior Changes" under the 6.30.0 relase in finagle.
- Wrong idenetation in util's cahngelog.
- Missing changelog for TwitterServer.

RB_ID=756329

BuoyantIO/twitter-server,BuoyantIO/twitter-server,BuoyantIO/twitter-server,twitter/twitter-server,twitter/twitter-server,BuoyantIO/twitter-server,twitter/twitter-server