Remove Instructions link in nav. Improve tab help.
Revise help text for the Trees tab.
Add help text for the Files tab.
Add help text for Tools tab and example tool links.
Cleanup OTU Mapping help and add project links.
Add help text for the Annotations tab.
Standardize menu text
Merge pull request #237 from OpenTreeOfLife/curation-help-text

Curation help text