Update and restore PhyloPic features in synth-tree viewer

[Jim Allman]

In building the new synth-tree webapp, I realized that we've long ago lost our PhyloPic icons for the current taxon. For now, we've opted to hide/disable these features, but it would be nice to restore them later using the current PhyloPic API:

• simple API "recipes" to try
• full API docs
• use SVG images??