Refactor collapsed view to preserve relation directionality

[goodb]

Consider a folded function node X such as 'Beta-catenin is released from the destruction complex' in http://noctua-dev.berkeleybop.org/editor/graph/gomodel:-80976963

Relations such as:
Z 'involved in positive regulation of' X and
X 'enabled by' Y

are shown to the user like:
'involved in positive regulation of' Z
'enabled by' Y

as if Z and X were switched, resulting in confusion. See geneontology/pathways2GO#18

When folding incoming relations, show instead something like
Z 'involved in positive regulation of'

[vanaukenk]

Closing for now. We can open a new ticket if the issue comes up again.