Fix issues #11 and #12

Changes are on top of @FelixGV fix_issue_7 branch.

* Issue #11 
  * added dependencies on `slf4j-api`, `logback` (runtime/test), and `jul-to-slf4j` (for jersey)
  * converted `System.out` and `System.error` to `logger.info` and `logger.error` accordingly
  * provided default `logback.xml` with simple console and rolling file appenders and `logback-test.xml` with console only appender
* Issue #12 
  * added windows-specific code to `org.schemarepo.TestLocalFileSystemRepository#cleanUp()`