[Edit] Java: Data Types + related entries

[Dusch4593]

Type of Edit (select all that apply)

Clarify unclear content and/or terms

Description (optional)

Add a section to the Java: Data Types entry about reference types, including:

• Annotations
• Arrays
• Classes
• Enumeration
• Interfaces

For the following entries, include info about how the given concept is one of the reference data types (hyperlink back to Java: Data Types entry):

• Arrays
• Classes
• Enums
• Interfaces

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