[maven-release-plugin] prepare release v2.8.0
[maven-release-plugin] prepare release v2.8.0

joychugh/stream-lib,joychugh/stream-lib,oertl/stream-lib,orneryhippo/stream-lib,tempbottle/stream-lib,tempbottle/stream-lib,oertl/stream-lib,smartpcr/stream-lib,orneryhippo/stream-lib,smartpcr/stream-lib