Take into account source directory from original configuration for the generated repository links (#152)

* Allow the test environment to keep the originally sat 'source' value.

* Add a test case and a fix for the ignored source setting in the configuration file.

* Prepend the TEST_DIR only when the source configuration is not set to an absolute path (making it absolute in the process)

* Fix the definition of the relative repository paths, and fix the test feature to properly use the configured source directory.

see #59