GBlocks style automatic identification of useful columns of an alignment

The GBLOCKS (http://molevol.cmima.csic.es/castresana/Gblocks.html) algorithm could be added either as a service or as a built-in routine. This algorithm is one of a variety of methods that have been developed for automatically selecting the most informative/useful regions of an alignment prior to performing further analysis (e.g. tree building).