[Doc] Improved description texts in Subject
[Refactor] Rename Subject#has_special_path to replace_path
[Refactor] Rename Subject#has_special_user_path to replace_user_path
[Refactor] Rename Subject#special_paths to replace_paths
[Readme] Documented what #context is doing
[Typo] Fixed a wrong spec description
[Refactor] Rename Bacon::Adapter#context to file_tree_spec_context
Delegate from Configuration instances to #file_tree_spec_context
[Readme] Documented the new & easier API
Bumped version to 0.5.0