docs + todo's
drop guava 18, it's causing a conflict


exception:

```
java.lang.IllegalAccessError: tried to access method
com.google.common.collect.MapMaker.makeComputingMap(Lcom/google/common/base/Function;)Ljava/util/concurrent/ConcurrentMap;
	 from class com.google.inject.internal.Annotations$AnnotationChecker
```

guava is still available as transitive through the maven-core
update tests