Attach (recommended) or Link to PDF file here:
http://mariovalle.name/SciViz/1-s2.0-S0097849310001846-main.pdf

Configuration:
- Web browser and its version: Using pdf.js from Node.js through npm package `pdfjs-dist`
- Operating system and its version: Windows 10 64bits
- PDF.js version: 2.6.347
- Is a browser extension: No

Steps to reproduce the problem:
1. Load the file in acrobat
2. In document properties look at the Author field: it is `Samuel Silva; Beatriz Sousa Santos; Joaquim Madeira`
3. Look at  Additional metadata > advanced > dc:creator. It is marked as `seq container` and contains the 3 authors.
4. Using the code below gives: `"Author": "Samuel Silva"` that is, only the first one. And `"dc:creator": "Samuel SilvaBeatriz Sousa SantosJoaquim Madeira"`, that is the three authors squashed together without separators.

What is the expected behavior? (add screenshot)
In both fields the three authors as a single string with some sort of separator between them. Note that other pdf files that contains multiple authors already have them as a single string with names separated by commas.

The code used:
```
var pdfjsLib = require("pdfjs-dist/es5/build/pdf.js");
var pdfPath = "http://mariovalle.name/SciViz/1-s2.0-S0097849310001846-main.pdf";
var loadingTask = pdfjsLib.getDocument(pdfPath);
loadingTask.promise
  .then(function (doc) {
    var lastPromise;
    lastPromise = doc.getMetadata().then(function (data) {
      console.log(JSON.stringify(data.info, null, 2));
      if (data.metadata) {
        console.log(JSON.stringify(data.metadata.getAll(), null, 2));
      }
    });
  });
```
"<rdf:Description rdf:about='61652fa7-fc1f-11dd-0000-ce81d41f9ecf' " +
      "xmlns:xap='http://ns.adobe.com/xap/1.0/' " +
      "xap:ModifyDate='2009-02-13T12:42:54+01:00' " +
      "xap:CreateDate='2009-02-13T12:42:54+01:00'>" +
      "<xap:CreatorTool>\\376\\377\\000P\\000D\\000F\\000C\\000r\\000e\\000a" +
      "\\000t\\000o\\000r\\000 \\000V\\000e\\000r\\000s\\000i\\000o\\000n" +
      "\\000 \\0000\\000.\\0009\\000.\\0006</xap:CreatorTool>" +
      "</rdf:Description><rdf:Description " +
      "rdf:about='61652fa7-fc1f-11dd-0000-ce81d41f9ecf' " +
      "xmlns:xapMM='http://ns.adobe.com/xap/1.0/mm/' " +
      "xapMM:DocumentID='61652fa7-fc1f-11dd-0000-ce81d41f9ecf'/>" +
      "<rdf:Description rdf:about='61652fa7-fc1f-11dd-0000-ce81d41f9ecf' " +
      "xmlns:dc='http://purl.org/dc/elements/1.1/' " +
      "dc:format='application/pdf'><dc:title><rdf:Alt>" +
      "<rdf:li xml:lang='x-default'>\\376\\377\\000L\\000&apos;\\000O\\000d" +
      "\\000i\\000s\\000s\\000e\\000e\\000 \\000t\\000h\\000\\351\\000m\\000a" +
      "\\000t\\000i\\000q\\000u\\000e\\000 \\000l\\000o\\000g\\000o\\000 " +
      "\\000O\\000d\\000i\\000s\\000s\\000\\351\\000\\351\\000 \\000-\\000 " +
      "\\000d\\000\\351\\000c\\000e\\000m\\000b\\000r\\000e\\000 \\0002\\0000" +
      "\\0000\\0008\\000.\\000p\\000u\\000b</rdf:li></rdf:Alt></dc:title>" +
      "<dc:creator><rdf:Seq><rdf:li>\\376\\377\\000O\\000D\\000I\\000S" +
      "</rdf:li></rdf:Seq></dc:creator></rdf:Description></rdf:RDF>" +
      "</x:xmpmeta>";
    const metadata = new Metadata(data);
    expect(metadata.has("dc:title")).toBeTruthy();
    expect(metadata.has("dc:qux")).toBeFalsy();
    expect(metadata.get("dc:title")).toEqual(
      "L'Odissee thématique logo Odisséé - décembre 2008.pub"
    );
    expect(metadata.get("dc:qux")).toEqual(null);