Fixed debug log message.
Replaced hardcoded hostname with proper invocation of UnixCloudHostListener.getHostName().
Added itests for all possible copy scenarios.
1. Unix vs Windows (handled by itest implementation classes).
2. File vs directory.
  * Destination directory with and w/o trailing slash (= x3)
3. Local source vs remote source.
4. Non-existing vs. existing destination.
  * Should merge when destination directory exists!
5. Destination name identical to same name vs. different.
Split OverthereConnectionItestBase into multiple classes to make it easier to work on a subset of the itest methods.