select/exclude sequences from alignment view by annotation

Following on from JAL-1065, it's useful to be able to include/exclude sequences from a view in the same way that columns can be excluded according to their alignment reliability score as calculated by T-Coffee.

Currently, the select by annotation uses a single annotation row to filter columns. In a per-sequence mode, the combo-box should group sequence associated annotation by name and so allow low scoring sequences to be included/excluded according to it's specific annotation row score, in an analogous fashion to the shading by per sequence annotation.