Fix syntax in OBO products

[althonos]

Hi !

The current release contains several syntax errors that make the OBO products invalid considering the OBO format version 1.4 specification:

• KEGG COMPOUND:XXX xrefs should be updated to KEGG_COMPOUND:XXX just like ChEBI did
• Several cases of full-text book references (such as Bolton, B. (1994). Identificstion guide to the ant genera of the world. Cambridge, Mass., Harvard University PRess. pp.1-222.")
• Invalid dbxrefs (such as The Pherobase: Database of Insect Phermones and Semiochemicals\:El-Sayed AM "http://www.pherobase.com")
• Invalid links in dbxrefs (such as WP:\:http\://en.wikipedia.org/wiki/Semiochemical)
• Invalid DOI format (e.g. XX:DOI\: 10.1086/522843)
• Placeholder dbxrefs (XX:<new dbxref>)

cc @cmungall