Support contact maps in GREMLIN format

Many people use the GREMLIN server for predicted contacts, which are output in a tabular format with a header line (example: http://openseq.org/sub_txt.php?id=1476807290).

Foldit can *almost* load this file, but requires two small revisions in the header line: You have to prefix the line with '##' and change the column name 'prob' to 'weight'. Is it possible to add support for parsing the raw GREMLIN output?