Block: remove unnecessary typename for an iterator

std::vector<Source>::iterator does not need an extra typename.
Having it will break the build for VS2013.
[win] VS2013 doesn't support noexcept. Workaround that.

Oh boy... ;-)
None.hpp: New header with our typedef of boost::none_t
[win] Use the global none_t from None instead of one per class

This should fix the build on windows again and close issue #118
Merge pull request #118 from gicmo/win32_fixes

First part of some build fixes for windows... cool