v0.1.0

Implement local files for go and chebi ontologies
Add "go_bp", "go_cc", "go_mf" as possible ontologies.
Rename chebi roles ontoloy as "chebi_r"
Add chebi classes ontology as "chebi"

Facilitate import :
Possible : "from ontosunburst import ontosunburst"

Modification of parameters :

delete "url_endpoint"
rename "root" to "input_root"
rename "class_ontology" to "ontology_dag"
rename "labels" to "id_to_labels"
add "labels" as bool

Correct package imports problems