List and Map augmentations: count and exists
Compliance with the development rules
List and Map augmentations : add some tests
Merge pull request #90 from k33g/wip/count_exists

List and Map augmentations: count and exists
Iterable augmentations: count and exists for tuples, sets and vectors
Merge pull request #91 from k33g/wip/count_exists_reloaded

Iterable augmentations: count and exists for tuples, sets and vectors