Ενδιάμεση επεξεργασία ροών

• Stream filter(Predicate predicate)
• Stream map(Function mapper)
• Stream flatMap(Function mapper)
• Stream distinct()
• Stream sorted()
• Stream peek(Consumer action)
• Stream limit(long maxSize)
• Stream skip(long n)
• Stream takeWhile(Predicate predicate)
• Stream dropWhile(Predicate predicate)