Method Chewy::Query#none for empty scope
empty_scope moved to options
Have renamed `empty_scope` to `none`
Merge pull request #7 from undr/none_method

Method Chewy::Query#none for empty scope
Move errors to separate file
Add repository
Make settings tricky
Make guard work
Rename Chewy::Repository::UndefinedItem to Chewy::UndefinedAnalysisUnit
Move repositories staff to config
Fix
Add #clear and #empty? methods to repository
Make specs green
Merge pull request #8 from webgago/tricky_settings

Tricky settings
Readme improvements
Improved `purge!` behavior
Version bump
Analysis resolving behavior changes
Version bump