Add current reference text and DOI to popup.

This allows easy comparison of current vs. proposed reference text and
DOI/URL in our CrossRef popup. Addresses #376.
Merge branch 'master' into DOI-lookup-with-comparison
Improved styles for argus tree view.

Addresses #44. Improvements include:
 - more distinct dashed (taxo) vs. solid (phylo) edges
 - third style for edges with taxo+phylo support
 - more conventional black-and-white scheme
Reserve true black for phylo-supported edges.

Also conflate path styles for all edges with phylogenetic support,
whether or not they are also supported by taxonomy. Addresses #44.
Text cleanup (per @jar398's suggestion)

See https://github.com/OpenTreeOfLife/opentree/issues/376#issuecomment-57717840
Split tree-viewer popup into three tabs.
Improved legend for tree-viewer popup. Fixes #390.
Relax the layout of tree properties in tree viewer
Merge pull request #470 from OpenTreeOfLife/DOI-lookup-with-comparison

Add current reference text and DOI to CrossRef popup.
Merge pull request #471 from OpenTreeOfLife/new-argus-styles

Improved styles for argus tree view
Merge pull request #473 from OpenTreeOfLife/tabbed-tree-viewer

Tabbed tree viewer
Merge branch 'master' into supporting-files-from-imported-trees