Fixed #683 - relations not exporting.

[KevinJump]

Fixes that relations don't get exported.

by default no relations are actually exported (because we don't export the default ones).

to enable them you have to set the exclude and include relations values.

"Sets": {
      "Default": {
        "Handlers": {
          "RelationTypeHandler": {
            "Settings": {
              "Exclude": "s",
              "IncludeRelations": "true"
            }
          }
        }
      }
    }

[KevinJump]

Fixes #638