Merge pull request #30 from tyx/master

Many improvements
Small improvement/refactoring

We need to make execution context more stupid and slim

Try to follow SRP
update examples
Merge pull request #31 from tyx/master

Move Units tests
update tests : ExtractorProxy
Alternative to BC Break ExecutionContext::getLogger

You can now get logger in exec options
Complete tests TransformerProxy/LoaderProxy
Merge pull request #32 from tyx/feature/simplification

Feature/simplification
Fix forgotten arguments
Merge pull request #33 from tyx/fix/piped-msg

Fix forgotten arguments