[Alpha] Version bump.
[Tasks] Todo added.
[Aux] Disable trace collecting by default.
[Unit Testing] Underflow and overflow test cases added.
[Bug Fix] Using `boost::numeric_conversion` instead of own velocycles.

This change allows to properly cast from other integer to another with precision loss/overflow/underflow detection. Magic!
[Tasks] Sadly, but `boost::format` is slow.
[Aux] Renaming and decoupling done.

Class `scoped_pump` (detail implementation) is now called 'pusher_t` and lives in its own file. Its factory function has been renamed.
Main macro definition lives now in `blackhole/macro.hpp`.
File `blackhole/log.hpp` is left for backward compatibility, but may be removed later.
Fixed tests, old usages and other stuff.
[Optimization] One task less.
[Aux] Using move semantics widely.
[Code Style] Styling and reordering.
[API] Streaming sink now allows to use custom `std::ostream`.
[Thread Safety] First look over thread safety concept.
[Code Clean] Code review: frontend.

Added some typedefs for readability. The code has been slightly reformatted. Variable renaming.
[Aux] Thread-safe concept review.
[Aux] Move message, maybe some sinks need its copy.
[Aux] There is no need for this code.
[Aux] Trait based smart thread-safety for sinks has been implemented.
[Code Style] Style.
[API] Null sink is thread-safe. Wow!
[Thread Safety] Files sink is thread unsafe.