ignore signature headers in constructors of anonymous inner classes

[jensdietrich]

Reproduce using commons-logging/commons-logging/1.3.0/commons-logging-1.3.0.jar (mvnc vs obs)

-IDB_METHOD_SIGNATURE	projected	org/apache/commons/logging/impl/WeakHashtable$1::<init>(Lorg/apache/commons/logging/impl/WeakHashtable;Ljava/util/Enumeration;)V	()V
+IDB_METHOD_SIGNATURE	projected	org/apache/commons/logging/impl/WeakHashtable$1::<init>(Lorg/apache/commons/logging/impl/WeakHashtable;Ljava/util/Enumeration;)V	null

This is a new soundy rule (although it is very unlikely that somebody accesses this using reflection). The IDB_METHOD_SIGNATURE instruction could either be just removed, or the signature (last slot) always be set to null.

[jensdietrich]

done, added new rule