ugly/gstlal_plot_channel_psd: file output names more sensible, fixed help comments to reflect changes

gstlal_idq_trigger_gen: added bottle routes, http server to produce psds, added verbose output; gstlal_plot_channel_psd: plotting utility for psd xml files

- simplify segment list collection
- fix handling of unpopulated segment list types

gstlal_idq_trigger_gen: modified trigger output to add true duration of template (instead of max duration)