Update the version management for Dctc.

* dctc-hash-update.sh,
  src/dctc/java/com/dataiku/dctc/configuration/Version.java: Use only
  one flag for the version management: `XXX_GIT_VERSION_XXX'. If no
  tag is found, use the default version 0.0.
ftp: The port is not a mandatory parameters.

* src/dctc/java/com/dataiku/dctc/file/FTPFileBuilder.java: Add a right
  value to the Params objects.