chore(AIP-191): add Rationale for Java options (#1365)

* chore(AIP-191): add Rationale for Java options

* address feedback

* remove rationale example

Author: noahdietz

aip/general/0191.md

@@ -127,8 +127,20 @@ which don't include compound names, be aware that _adding_ this annotation
 (with a value not equivalent to the default) constitutes a breaking change in
 that language. When releasing protos, be sure that omissions are intentional.
 
+## Rationale
+
+### Java packaging options
+
+Set the option, `java_multiple_files`, to true to get a cleaner file structure.
+Doing so instructs `protoc` to create one output file per Protobuf type, which
+allows for more fine-grained imports. The option, `java_outer_classname`, is
+required in combination with `java_multiple_files`. It instructs `protoc` to
+wrap each compiled Protobuf type in a Java class whose name is the value of the
+option. This prevents potential naming collisions between generated types.
+
 ## Changelog
 
+- **2024-06-05**: Added rationale for Java packaging options.
 - **2023-02-24**: Added guidance on protobuf syntax.
 - **2022-10-18**: Added guidance on Ruby/PHP/C# options.
 - **2019-11-18**: Added guidance on the packaging annotations.