* update to hooks
* more class to function
* cleanup
* finish ts final
* update html lesson
* add lessons page
* clean up
* move getters into context
* adding type
* fix bug
* step 5 cleanup
* init final pass
* text tweak
* fix ternaries
* readme cleanup
* fixed root readme
* Fix Step1/04 - React Intro - final
Problem:
1. Customized Button.tsx is not used in Counter.tsx
2. index.tsx still renders the 'hello world' text
Fix:
1. Use customized Button.tsx in Counter.tsx
2. Have index.tsx render the App component instead of 'hello world' text
Notes:
Validated customized button now show correctly.
* Add missing blank line.
