Add CondFormats/External and CondFormats/Serialization.
Cleanup externals in light of BOOSTIO migration.
Add test
One more utility.
Rest of the BOOSTIO fixes.
Add headers.h
Add tests.
Add SerializationManual.h.
Add serialization manual.
Fix CondFormats/JetMETObjects/src/classes.h
Add empty file.
Support for clang 3.4
Remove need for empty Serialization.cc files.
Add serialize method.
Merge pull request #3691 from ktf/initial-merge-of-boost-io

Initial merge of boost io