update readme, smal rules corrections

README.md

flowchart.png

maven-template-jdk17/src/main/java/ch/hepia/App.java

...-template-jdk17/src/main/java/ch/hepia/BlackJackHand.java

maven-template-jdk17/src/main/java/ch/hepia/GameManager.java

maven-template-jdk17/src/main/java/ch/hepia/Human.java

maven-template-jdk17/target/classes/ch/hepia/App.class

...emplate-jdk17/target/classes/ch/hepia/BlackJackHand.class

maven-template-jdk17/target/classes/ch/hepia/Dealer.class

...-template-jdk17/target/classes/ch/hepia/GameManager.class

maven-template-jdk17/target/classes/ch/hepia/Human.class