Delphi ProtoBuf files generator

by @modersohn (https://github.com/modersohn)

• support for optional fields
• strong check for fill all required fields
• minimize and beautify the generated code

Add console generator version

Add example

Work with binary ProtoBuf messages based on https://sourceforge.net/projects/protobuf-delphi/files/ by marat1961 (sources have some modifications)

Main features:

• generate classes, not records (like most other parsers)
• cross-platform(???) realization

Limitations:

• no comments in the middle of declaration:

  // this is correct
  message Sample { // this is correct
    // and this too
    repeated // this is NOT supported (comment in the middle of field declaration)
      sint32 Foo = 1;
    optional string FooString = 2; // this is correct

• field types Any and OneOf not supported

• reserved word extensions not supported

• groups (deprecated feature) not supported

• add root folder of this project to library path (Tools - Options - Delphi options - Library)
• open ProtoBufGeneratorGroup.groupproj from root folder of this project
• compile and run ProtoBufGenerator.exe
• open .proto file(s) by press "Open" button
• select directory for new generated .pas file(s) and press "Generate" button
• add generated file to your project.

Do not use LoadFromBuf/SaveToBuf methods in generated classes! Use LoadFromStream and SaveToStream methods, which inherited from base class. See Example2, how to use generated classes.

• add extensions (simple ignore directive, or - wrap to comment)
• add tests with "original" ProtoBuf generated binary messages.