Ontohub: new tables and views

crucial prerequisites:

* repair new model branch, Henning, Daniel

* read in DGXML (produced by Hets) #55 Julian, Till (example needed)

* read in Ontohub registry (RDF) #62

* display graphs (e.g. via graphviz) #63

existing tables

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ontologies

* show local theory by default, button for showing flattened theory

* translate ontology to different language

* for distributed ontologies, show members

* divide sentence numbers into axioms, theorems and goals

* adding new axioms + goals

* check consistency (via Hets)

* union of n ontologies

* filter by logic/language

* class graph (see Bioportal)

ontology_versions

links

* CRUD + ownership

* show ontology graph, say, up to three links from the current ontology (larger diameters may be input by the user). Use graphviz/svg

* check conservativity (via Hets)

link_versions

sentences

* show proof status and basic_proofs

* for goals, add prove + disprove buttons (via Hets)

metadata

permissions

users

entities

entity_mappings

entities_sentences_table

teams

team_users

comments

new tables

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logics

* CRUD + ownership + supports relation

logic_mappings

* CRUD + ownership + logic_adjoints

* show logic graph (and interesting subgraphs)

languages

* CRUD + ownership + supports relation

language_mappings

* CRUD + ownership + language_adjoints

* show language graph (and interesting subgraphs)

serializations

* CRUD + onwership

basic_proofs

* show, including uses sentences

structured_proofs

* show, including parts

structured_proof_parts

* see structured_proofs

used_sentences

* see basic_proofs

logic_adjoints

* see logic_mappings

language_adjoints

* see language_mappings

supports

* see logics + languages

members

* see ontologies