Release 0.2.0

- Add parameter message to Boolean
- Add message parameter to IsNumeric
- Add message parameter to IsNull
- Standardize default rule messages
- Remove unused dependency to Doctrine/Collection
- Add message parameter to IsArray
- Add IsIPAddress Rule
- Add message Parameter to MaxLength rule
- Add IsInChoice rule
- Add IsURL rule
- Add NotEmpty Rule

Release 0.1.0