Character encoding / CSV reprojection

I've got PR's for the main repo coming for `kr-seoul`, `us-or-portland`, and `au-victoria` and I'm afraid they all depend on this PR.
- adds support for `iconv` character encoding adjustment
- allows reprojection of CSVs & geoJSON (previously only supported this operation for shapefiles)
- adds a few new operations to source.conform, which are documented in the README (all existing ones are untouched)
- tests for above (testing reprojected geoJSON TBD)
- includes commits from the `unzip-fix` PR, should be up to date with `master`