Add summary data of system-level C. elegans to openworm/owmeta-data bundle

[slarson]

Incorporate the facts from this spreadsheet into the openworm/owmeta-data bundle.

Requirements:

• Must include references listed in the document as appropriate Document/Evidence
• Must use DataSource / DataTranslator for translating from the spreadsheet
• May use the spreadsheet directly from Google Sheets or download it
• Must include the ranges for values, where listed, rather than individual values within those ranges
• Must merge existing Document objects with the new ones created: search for documents already in the database and re-use the URIs.

Recommendations:

• Should verify that the facts and figures are faithfully reproduced from the references.

[mwatts15]

Can attach facts to the main Worm object or the Network as appropriate. Create property types for each one...