Enable orthoxml export on Gene Tree page as well as homologue alignments pages
Fixed missing options for tree formats
OrthoXML no longer takes any options
Use new settings structure with values from viewconfig
Get relevant parameters from viewconfig where available
Refactor to use form_fields instead of form method
Display options not needed for export - however changed wording to be consistent within the form
Removed unneeded parameters (used for visual display only)