Updated email address to miguel@miguel-martin.com in README.
As this this the email address I frequently check now.
Updated README's tutorial: removed references to slot::bind;
now is a bit easier to follow (IMO).
Addded usage of std::forward where appropriate.
Fixed compilation error caused by using std::forward.
Assumed std::forward would auto-deduce it's type for overload,
i.e. I thought std::forward(args) would work, but you have to
explicitly write std::forward<Args>(args)
Added a makefile to auto-compile benchmark.