- Instead of repeating code between import info from list and import
  info, include a type guard on import_info to check if the argument
provided is a path or a just a string.

- Addresses lubianat#14

- Keeps both commands, but refactors repeated functionality into a
  separate function.
- Also improves the way the path to the ORCID file is read
- Also adds missing open_browser to import_list

- Closes lubianat#14

- This way the same option code isn't repeated between modules, it's
  merely passed down as context
- Open browser can now be called as:
`pyorcidator --open-browser import --orcid ORCID_ID`