[Benchmark] Proof, that there is other way to make logger faster.
[Aux] Massive log record refactoring.

Inner attribute set is now completely incapsulated. Log record can
return const reference to it if needed. Also setter method added.
[Code Style] Drop unnecessary typedefs.
[API] Dropped unlikely initializer list constructor.
[Code Style] Log record  and attribute pack feeder traits have been refactored.
[Documentation] More documentation added.
[Tasks] More testing tasks.
[Performance] Increased performance.

Previously, when opening record occurred, there were multiple attribute sets initialized and merged into the single one.
After profiling it has been revealed that this action was one of the heaviest for record opening.

Now multiple attribute sets is aggregated into single `view` class, and attribute lookup is performed when it is needed by someone.

The code is really dirty at this moment, so it needs some love.
[Aux] Garbage collection.
[GCC 4.4] Fixed compatibility with my old friend.
[Code Style] Style.
[Aux] Dead code elimination.
[API] No more `blackhole::log::*` namespace.
[API] Decomposition done over attribute value.
[Bug Fix] Forgotten include.
[Aux] Trait decomposition.
[Aux] Some notes added.
[Aux] Decomposing attribute name. Deprecation warning added.
[Aux] Some cross-platform stuff added.
[Aux] Fix deprecation warning.