1.0.0-pre3

This pre-release brings several fixes and API improvements to the base library.

Fixes

• required option now works for oneof fields [#240];
• repeated fields now may be included in FieldMasks [#250];
• removed ValidatingBuilders for standard types [#252];
• removed modelCompiler. generateBuildersFromClasspath [#252];
• ValidatingBuilders generation attempts are dropped and warnings are not logged any more [#268].
• generated field annotation lookup bug is fixed [#269];
• ValidatingBuilders for nested types are now generated [#272];
• constraint validation error messages are now more readable [#279];

API improvements

• (is) and (every_is) options now allow implementing existing Java interfaces [#248];
• introduced (set_once) field option, which does not allow to change the value of a field after it was once set [#257, #275];
• numeric and boolean Protobuf types do not support (required); a message is logged on the option misuse; [#266];
• generated identifier types now support factory methods for convinience [#267];
• generated code is now marked with Java annotation types which can be specified [#280];
• selected generated methods and classes now can be marked as @Internal [#284, #287].