Use all parameters for logging.
Minor change, add "FIXME".

- Split up arguments for "import" into separate lines to improve readability.
- Add a "FIXME" that needs to be discussed with Daniel.
Use escapeshellarg() to do the escaping job.

refs #236, #233
Add credentials implicitly as they are required anyway.

- buildCmd() has two arguments now, the actual command and (optionally) an
  array of parameters that can be required by the wrapper script.
- Authentication credentials are now added automatically as anyway all wrapper
  commands require them.

refs #236, #108
Add documentation for buildCmd().

refs #236, #108
Use buildCmd() to simplify buildCredentialsCmd().

refs #236, #108
Use buildCmd() to simplify buildTreeCmd().

refs #236, #108
Use buildCmd() to simplify buildExportCmd().

refs #236, #108
Use buildCmd() to simplify buildImportCmd().

refs #236, #233, #108
Add "FIXME", requiring discussion.

refs #108