simplify description of how to make lazy functions

svn path=/trunk/libs/proto/; revision=77446
use decltype-based result_of if and only if the compiler implements N3276

svn path=/trunk/boost/proto/; revision=77873
c++11, force parameter to mpl::eval_if_c and mpl::if_c to be bool

svn path=/trunk/boost/proto/; revision=78122
c++11, force parameter to mpl::if_c to be bool

svn path=/trunk/boost/proto/; revision=78141
disable '__forceinline not inlined' warning on msvc

svn path=/trunk/boost/proto/; revision=78196
fix minor typos

svn path=/trunk/libs/proto/; revision=78835
transforms get pseudo-parameter pack expansion support for unpacking expressions

svn path=/trunk/boost/proto/; revision=79461
reference docs for pseudo-pack expansions in transforms

svn path=/trunk/boost/proto/; revision=79465
user docs for unpacking patterns in transforms

svn path=/trunk/boost/proto/; revision=79485
tests for proto::protect

svn path=/trunk/libs/proto/; revision=79567
add support for transform environment with slots for key/value pairs

svn path=/trunk/boost/proto/; revision=79632
add reference section for new transform environment functionality

svn path=/trunk/libs/proto/; revision=79678
user docs for transform environments

svn path=/trunk/libs/proto/; revision=79686
add release notes for 1.51 (unpacking patterns) and clean up example in unpacking patterns section

svn path=/trunk/libs/proto/; revision=79703
move transform environment-related classes into ADL-blocking namespaces

svn path=/trunk/boost/proto/; revision=79711
oops, use BOOST_PROTO_RESULT_OF instead of boost::result_of

svn path=/trunk/boost/proto/; revision=79713
fix multiple defs linker error

svn path=/trunk/boost/proto/; revision=79725
missed this in the last check-in, darn

svn path=/trunk/boost/proto/; revision=79742
don't use B0, conflict with a macro on Linux, references #7203

svn path=/trunk/boost/proto/; revision=79918
workarounds for earlier gcc flavors

svn path=/trunk/boost/proto/; revision=79920