Consider to propagate deprecated tag into generated code

[mikir]

Deprecated tag in classic documentation comment is currently not propagated into generated code. Example:

/**
 * This is some structure.
 *
 * @deprecated
 */
struct DirectionStructure
{
};

Generated Java code (with comments):

/**
 * This is some structure.
 * <p>
 * <b>Deprecated</b>
 */
public class DirectionStructure implements zserio.runtime.io.InitializeOffsetsWriter, zserio.runtime.SizeOf
{
}

Javadoc annotation @deprecated is not used because Java will fire warning that Java annotation @Deprecated should be used as well.

The similar problem is in C++ for clang.

Python Sphinx deprecated tag is not used because it requires version.