add 'why?' menu item

CONTRIBUTING.md

@@ -35,7 +35,7 @@
      *  try to add examples for mainstream cases and some edge cases
      *  start with an element for the `import` statement, followed by an empty string element
      *  follow up with usage examples, one element per example 
-* Finally run `yarn generate-readmes` or `npm run generate-readmes` to update all READMEs with your changes.    
+* Finally run `yarn generate-readmes` or `npm run generate-readmes` to update all READMEs with your changes.
 
 # App Testing
 [Raul Melo](https://github.com/raulfdm) has written [a nice test framework](https://github.com/devraul/just-test) for testing cjs and esm imports of Just utilities in a variety of common app environments. Take advantage of this if you want to test how a module will work in the context of a given app.

README.md

@@ -3,7 +3,7 @@
 
 # Just
 
-## [Docs](#the-modules-package) | [Try It](https://anguscroll.com/just) | [Contribute!](https://github.com/angus-c/just/blob/master/CONTRIBUTING.md)
+## [Docs](#the-modules-package) | [Why?](#read-books) | [Try It](https://anguscroll.com/just) | [Contribute!](https://github.com/angus-c/just/blob/master/CONTRIBUTING.md)
 
 A library of **zero-dependency** npm modules that do just one thing.
 A guilt-free alternative to those bulkier utility libraries. Ideal for PWA development or whenever bytes are precious.

templates/global.template

@@ -1,6 +1,6 @@
 # Just
 
-## [Docs](#the-modules-package) | [Try It](https://anguscroll.com/just) | [Contribute!](https://github.com/angus-c/just/blob/master/CONTRIBUTING.md)
+## [Docs](#the-modules-package) | [Why?](#read-books) | [Try It](https://anguscroll.com/just) | [Contribute!](https://github.com/angus-c/just/blob/master/CONTRIBUTING.md)
 
 A library of **zero-dependency** npm modules that do just one thing.
 A guilt-free alternative to those bulkier utility libraries. Ideal for PWA development or whenever bytes are precious.