* fix: compilation of move support up to vc11

Visual Studio compilers up to VS2012 don't auto-generate move constructors and move assignment operators. One has to implement them manually.

Signed-off-by: Daniela Engert <dani@ngrt.de>
Merge pull request #2 from DanielaE/fix/vc-move-support

* fix: compilation of move support up to vc11
Removed unreachable code.
Removed redundant #define.
Removed redundant forward declaration of slot class when
compiling with variadic templates.