Checkstyle java8

Sputnik 1.2 utilizing experimental [Sabaka checkstyle](https://github.com/sabaka/checkstyle/ "Sabaka checkstyle")

Added support for Java8-specific syntax in checkstyle

[Issue 10. Java 8 syntax support has been added #226](https://github.com/checkstyle/checkstyle/pull/226 "Sabaka checkstyle")