Added a small comment for make()
Added doxygen generation
Removed @ref from std::unique_ptr

since references to standard library constructs cannot be found by
doxygen
Added param_tuples module to docs.
This test now builds with clang3.3
Don't need to include <chrono>
Renamed error to unexpected. Did some refactoring.
Removed useless using statement
Initial files for type_traits
Implemented predicate_and
Implemented predicate_or
Beginnings of relate
Added exists and forall modifiers.
Started unit tests.
Relate coming along nicely.

Still need to implement/test using forall/exists for both arguments.
Base case tests for double forall/exists support
Test cases for relate(forall, forall)
Unit tests for relate(forall, exists)
Unit tests for relate(exists, forall) and relate(exists, exists). Unit
tests complete.
Implemented basic binary relations