Multiple changes to disentangle epi and endothelial cells (#2423)

* Multiple changes to disentangle epi and endothelial cells

Some sidetrack into work on fenestrated endothelial cells.
Still to do - various kidney cells - where ellithelium vs endothelium may become ambigous?

* More cleanup to remove endothelial under epithelial cell

Also cleaned up 'squamous endothelial cell', which was used to refer only to the squamous endothelial cells of venules.  There is now a new dedicated term for this.  The definition of the existing term is now generic, as implied by the name.

* Updated imports to pull in new PATO term

UPdated imparts

* Fixed AP check violation.

* Orcid is now IRI

* Update cl-edit.owl

Fixed some minor issues with synonyms and def text.
Fixed some issues with endothelial cell classification.

* Update cl-edit.owl

deleted accidentally injected axiom on PATO term I'm trying to import.

* Fixing syntactical fubar of mysterious. origin

Was Protege responsible?

* Update cl-edit.owl

OK.  Now it's fixed?  Quotes now *inside* brackets delimiting ofn clause.  Doh!