Apply camel case convention

src/main/java/re/forestier/edu/rpg/Adventurer.java

src/main/java/re/forestier/edu/rpg/Affichage.java

src/main/java/re/forestier/edu/rpg/Archer.java

src/main/java/re/forestier/edu/rpg/Dwarf.java

src/main/java/re/forestier/edu/rpg/Player.java

src/test/java/re/forestier/edu/UnitTests.java