Highlight phosphorylations and include information about site mapping in HTML assembler

[cthoyt]

Statements like MAPT is phosphorylated on S579 don't have mechanistic information, but are definitely interesting and informative. However, when they go through the HTML assembler, they are more difficult to understand than binary statements like MEK phosphorylates ERK. There are two suggestions I would make to improve legibility:

1. Highlight the text positions describing the modification type and position (if/when available from the reader)
2. Add a mouseover on the text that explains, when applicable, why the site mapper modified the numbering.

Examples available here: https://db.indra.bio/statements/from_hash/9106400304539467?format=html

[bgyori]

Thanks, these are good ideas! Currently not on the critical path, but we'll keep them in mind.