Add missing includes to SerializationManual.h

[Teemperor]

We use the different Histogram classes in this header, so we
also need to import the different definitions for each.
For simplicity I just added one include for Histogram3D because that's
also including the other Histogram classes.

[Teemperor]

Part of the work to solve the issue #15248

[cmsbuild]

A new Pull Request was created by @Teemperor (Raphael Isemann) for master.

It involves the following packages:

CondFormats/PhysicsToolsObjects

@ghellwig, @arunhep, @cerminar, @cmsbuild, @franzoni, @ggovi, @mmusich, @davidlange6 can you please review it and eventually sign? Thanks.
@ghellwig, @tocheng this is something you requested to watch as well.
@davidlange6 you are the release manager for this.

cms-bot commands are listed here

[ggovi]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/19912/console Started: 2017/05/17 12:15

[ghellwig]

+1
trivial change

[cmsbuild]

+1
Tested at: ea1db0a
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-18784/19912/summary.html

[cmsbuild]

Comparison job queued.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-18784/19912/summary.html

Comparison Summary:

• No significant changes to the logs found
• Reco comparison results: 3368 differences found in the comparisons
• DQMHistoTests: Total files compared: 24
• DQMHistoTests: Total histograms compared: 1833867
• DQMHistoTests: Total failures: 33929
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 1799758
• DQMHistoTests: Total skipped: 180
• DQMHistoTests: Total Missing objects: 0
• Checked 98 log files, 14 edm output root files, 24 DQM output files