RemoteServer + RESTClient

1) Added RemoteServer and RESTClient modules into root pom for including new items into common build life-cycle.
2) Added remote interfaces to sikuli package, as both client and server uses them.
3) Splitted embedded Client into separate module - RESTClient.
4) Revised several project areas to allow Java 7 compatibility: removed lambdas, streams and defaults in interfaces.
5) Added BaseTest wrapper for adding single start / end point for all tests and avoid code duplication.
6) Added more details into README.md.
7) Revised resources hierarchy.
8) Added maven-surefire-plugin support to simplify test execution process.
9) Disabled tests by default to avoid accidental failures before finishing setup.
10) Minor bug fixes.