iteminfo.py: eat RuntimeError from CharacterInfo

Requesting CharacterInfo on a not-character started throwing at some
point:

  File "/home/scot/dev/git/electusmatari.com/lib/mrintel/eve/iteminfo.py", line 464, in info_character
    charinfo = apiroot.eve.CharacterInfo(characterID=charid)
  File "/home/scot/dev/git/electusmatari.com/lib/eveapi.py", line 277, in __call__
    return self._root(self._path, **kw)
  File "/home/scot/dev/git/electusmatari.com/lib/eveapi.py", line 343, in __call__
    raise RuntimeError("'%s' request failed (%d %s)" % (path, response.status, response.reason))
RuntimeError: '/eve/CharacterInfo.xml.aspx' request failed (500 Internal Server Error)

For now eating the RuntimeError makes things work better.