check if filename validation is needed and if so, write helper

[adswa]

During manual dataset creation, "upload via the web interface" allows to specify a "file path", a "hierarchical directory structure path used to display file organization and support reproducibility". An uploaded file will be placed under the file path given in this path. E.g., uploading "myfile.txt" and supplying "this/is/a/path/" results in the downloaded dataset to be a zip file with the directory tree this/is/a/path/myfile.txt. (dones't affect its visualization on dataverse it seems, there is it a flat list of files). This file path has character restrictions:

Directory Name cannot contain invalid characters. Valid characters are a-Z, 0-9, '_', '-', '.', '', '/' and ' ' (white space).

If we make use of these paths, we need a helper to ensure only valid characters are used. File names seem to be fine with non-valid characters, e.g., I was able to publish a file with an "ü" in the demo instance

[mih]

I think this is related to #83. Filenames are only exposed for exports (otehrwise the filenames are annex-keys, and there are no directories.

I believe a "validation" approach is not optimal. If a particular directory name is invalid for dataverse, what is a user supposed to do? If we force people to rename, they might run into validity issues with other services or organization standards.

I think, rather than failing on invalidity for dataverse, we should implement directory name mangling and unmangling on/from an export.

[mih]

I am closing this issue in favor of #83