Rename EnumSet to enum_set
Rename EnumTraits to enum_traits
Adopt STL naming convention in ErrnoHelper.hh
Adopt STL naming convention in ErrorLevel.hh
Remove FUNCTIONAL_INITIALIZE

It doesn't look very useful...
Adopt STL naming convention in FunctionalInitialize.hh
Remove unused IDENTITY
Rename Identity to identity
Adopt STL naming convention in IntegerSequence.hh
Rename Nop to nop
Adopt STL naming convention in TypeTag.hh
Adopt STL naming convention in Variant.hh
Adopt STL naming convention in VariantTest.cc
Adopt STL naming convention in Maybe.hh
Rename MaybeTest.cc to maybe_test.cc
Adopt STL naming convention in maybe_test.cc
Adopt STL naming convention in Message.hh
Rename OutputStream to xostream

Like xchar and xstring.
Adopt STL naming convention in Reference.hh
Adopt STL naming convention in SharedFunction.hh