Clusters With Non-existant Longest GI

[lcoghill]

Currently the longest sequence in some clusters, isn't listed in the sequences table. This is due to the fact that the sequences themselves have had their GIs corrected where as not all of the original clusters have. There are also some sequences that were purged before alignments and tree building due to various reasons, so it's possible the longest sequence was lost in the process.

Simple fix. Rebuild the clusters table, checking the longest GI against the sequences table. If it's not there, use the second longest, etc.