docs: adds additional stretch details

Signed-off-by: Anthony D. Mays <[email protected]>

Author: anthonydmays

lesson_10/README.md

@@ -16,15 +16,16 @@
 ## Homework
 
 * Read HFDP 1-2.
-* Complete [Applying SOLID principles](#applying-solid-principles) exercise.
+* Complete [Applying SOLID principles](#applying-solid-principles-library-management-system-part-ii) exercise.
 
 ## Applying SOLID Principles (Library Management System, Part II)
 
 In this assignment, you will be given starting implementations for the `Library`, `Book`, and `Patron` classes. You will need to add the following enhancements to support new functionality:
 
 * We now want to support the concept of a `Librarian`. A librarian should be able to check out or check in books just like other patrons. Books can no longer be added or removed from the `Library` without a librarian.
 * We also want to support other types of media formats, including `Dvd`, `Magazine`, and `Newspaper` types. Patrons cannot check out `Magazine` or `Newspaper` items.
-* [Stretch] Add the ability to search for items in the library by title, ISBN, author, or type. Extra credit will not be assigned unless the previous requirements have been met.
+* [Optional Stretch] Add the ability to search for items in the library by title, ISBN, author, or type. Extra credit will not be assigned unless the previous requirements have been met.
+* [Optional Stretch] Add the ability for patrons to be members of multiple libraries. See previous note on extra credit.
 
 You will need to make changes to code in the [solid/][solid-folder] sub-folder and submit your PR for credit. Don't forget to follow the Conventional Commit spec for your commit messages and pull requests title and descriptions.