fixed bug with library function calls

src/avatartranslator/AvatarAttribute.java

src/avatartranslator/AvatarLibraryFunction.java

src/avatartranslator/AvatarLibraryFunctionCall.java

src/avatartranslator/AvatarSimpleGuardDuo.java

src/avatartranslator/AvatarSimpleGuardMono.java

src/avatartranslator/AvatarStateMachine.java

src/avatartranslator/toproverif/AVATAR2ProVerif.java