Log Message:
2.8.0 (stable)
* Documentation: Mention use with CMake.

2.7.2 (unstable):
* Deprecate sigc::ref() and sigc::reference_wrapper(),
  adding support instead for std::ref(), std::cref(),
  and std::reference_wrapper().
* mem_fun(): Deprecate mem_fun(pointer, func).
  Leaving just mem_fun(reference, func).
  Please let us know if you disagree strongly with this.
* Make all operator bool() explicit. (A C++11 feature.)
* Build: Remove some now-unnecessary configure checks.
  But please let us know if this causes problems for you.
* Build: Update MSVC project.
* Documentation: Improve the documentation of mem_fun(), making it clear that
  mem_fun() does not return a slot.

2.7.1 (unstable):
* signal: Add a moving connect() method, taking an rvalue reference
  to a slot.
* can_deduce_result_type_with_decltype: Rename the check() methods to
  checksize(). check() is a preprocessor macro in Mac OS X.
* Temporarily undefine the nil macro, if it's defined.
  nil is a preprocessor macro in Objective-C++ and Mac OS X.
* Correct the mem_functor<> declarations.