String trimming only considers space and tab

[scpeters-test]

Original report (archived issue) by Sean Curtis (Bitbucket: SeanCurtisTRI).

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In the sdf::trim function, it is trimming off leading and trailing space and tab characters. I'd recommend going further in capturing all characters that C++ considers to be whitespace. Something like:

std::string trim(const std::string& name) {
  std::regex trim_regex("^\\s*(.*?)\\s*$");
  std::smatch matches;
  std::regex_match(name, matches, trim_regex);
  return matches[1].str();
}

Also, we might want to consider what whitespace is allowed inside strings. It would be silly to have a name: "a\f\vb".