Intercropping: Support multiple trait ontologies

[dwaring87]

For our oat/pea intercropping trials, the trait observations include some oat-specific traits and pea-specific traits. For now, we've been adding the pea-specific traits to the composed trait ontology (to keep the oat trait ontology clean and in-sync with cropontology.org). We'd like to be able to have additional trait ontologies loaded in the database (oat trait ontology, pea trait ontology, composed trait ontology) so each crop has a separate trait ontology.

Requirements:

• Be able to load additional trait ontologies into the database (should already be possible?)
• Tag the additional trait ontologies as a trait_ontology in the cvprop table
• Ensure the additional trait onologies are displayed on the Search > Traits page
• Ensure that traits from the additional trait ontologies can be used when uploading trait observations
• Ensure that traits from the additional trait ontologies are included in the BrAPI endpoints (and field book)

[dwaring87]

Duplicate of #4262