create hets instance if needed
style changes
fix description-reading for logicgraph-parsing

The characters method can be called multiple times in order to retrieve
the full text (like chunks) so we'll need to concatenate the results.
let description for logicgraph default to nil

This is needed for possible updates of description
on subsequent runs of the logicgraph-parsing.
respect newlines when displaying logic description.
abort ontologies only if they are not ontologies

Basically if hets determines that a file is not an ontology file
(catalogs for example), we'll need to abort the processing. In every
other case we should re-raise the original error.
Merge pull request #1117 from ontohub/1022-hotfix_aborting_of_ontologies

1022 hotfix_aborting_of_ontologies
Merge pull request #1091 from ontohub/1088-fix_logicgraph_parser

1088 fix logicgraph parser
Merge pull request #1097 from ontohub/add_hets_instance_generation_to_deploy

create hets instance if needed
use obo-label-names in sentences as well

This is solved by just calling set_display_text! on the
sentences at the right time (after the display_name for
the symbol has been updated).
add migration to update display_text of obo

Add the migration the update the display_text
of already existing obo sentences.
set displaytext in sentence only if non-nil.
optimize set_display_text! body.
Merge branch '1099-label_symbols_in_obo_sentences' into develop

Conflicts:
	lib/capistrano/tasks/deploy.cap
	lib/logicgraph_parser.rb
	lib/tasks/hets.rake