ajout des en-têtes et add/rm/md method et signal

src/main/java/avatartranslator/AvatarMethod.java

.../java/avatartranslator/mutation/AddAttributeMutation.java

...ain/java/avatartranslator/mutation/AddMethodMutation.java

src/main/java/avatartranslator/mutation/AddMutation.java

...ain/java/avatartranslator/mutation/AddSignalMutation.java

...ain/java/avatartranslator/mutation/AttributeMutation.java

src/main/java/avatartranslator/mutation/AvatarMutation.java

...n/java/avatartranslator/mutation/BlockStructMutation.java

...n/java/avatartranslator/mutation/MdAttributeMutation.java

...main/java/avatartranslator/mutation/MdMethodMutation.java

src/main/java/avatartranslator/mutation/MdMutation.java

...main/java/avatartranslator/mutation/MdSignalMutation.java

src/main/java/avatartranslator/mutation/MethodMutation.java

...n/java/avatartranslator/mutation/RmAttributeMutation.java

...main/java/avatartranslator/mutation/RmMethodMutation.java

src/main/java/avatartranslator/mutation/RmMutation.java

...main/java/avatartranslator/mutation/RmSignalMutation.java

src/main/java/avatartranslator/mutation/SignalMutation.java

...l/src/test/java/avatartranslator/AvatarMutationTests.java