Change version to 0.3.1-alpha
Add Hibernate's Email, NotEmpty and Length validator writers
Change ValidatorWriter to take LanguageContext instead of DataWriter

This enables more flexible output
Add support for returning refexp via JSON
Fix validator writer JSON tests

Set writer to JSON mode and added quotes around keys
Refactor ValidatorWriterManager to take collection of writers

This new way of creating ValidatorWriterManagers makes the code more
generic and allows user to easiely configure what validator sets user
wants to use. Previously user had to create complex hierarchies if
user wanted to use multiple sets of validator writers.
Rename BaseValidatorWriterManager to ValidatorWriterSet
Change version to 0.4.0-alpha
Rename ValidatorProcessor builder method to match it's arguments
Update documentation

Updated README.md documentation
Fixed minor bugs in JavaDocs
Fix IDEA inspection issues
Simplify ItemStatus equals
Fix minor issues with README.md
Add package dependencies image to README.md
Move remove setFieldValueConverter from BackboneModelProcessorBuilder

The fieldValueConverter should only be added to necessary ModelProcessors
Fix concurrency issues with BaseModelCache
Add new style BaseValidatorWriter that takes raw annotations
Fix minor inspection issues
Add filter mode setting to ModelProcessor
Add new exception class for invalid class implementations