FLUME-2533: HTTPS tests fail on Java 6

(Hari Shreedharan via Jarek Jarcec Cecho)
FLUME-2525. Handle a zero byte .flumespool-main.meta file for the spooldir source.

(Johny Rufus via Hari)
Updating CHANGELOG for 1.5.1 release
Preparing for Flume-1.5.1 Release
FLUME-2505: Test added in FLUME-2502 is flaky

(Hari Shreedharan via Jarek Jarcec Cecho)
FLUME-2497. Support fractional seconds in Syslog timestamps

This fixes a bug in the SyslogTcpSource and SyslogUdpSource where
fractional timestamps fail to parse.

(Johny Rufus via Mike Percy)
FLUME-2385. Remove incorrect log message at INFO level in Spool Directory Source.

(Phil Scala via Hari Shreedharan)
FLUME-2548: Enable SSLv2Hello for Avro Source and NettyAvroRpcClient

(Hari Shreedharan via Jarek Jarcec Cecho)
FLUME-2549: Enable SSLv2Hello for HttpSource

(Hari Shreedharan via Jarek Jarcec Cecho)
FLUME-2551. Add dev-support directory to source tarball.
Update RELEASE-NOTES for 1.5.2
Update CHANGELOG for 1.5.2
FLUME-2538. TestResettableFileInputStream fails on JDK 8.

(Johny Rufus via Hari)