Fixes unroll translations
Adds density calculator
Merge branch 'master' of github.com:ekylibre/ekylibre

Conflicts:
	config/locales/arb/nomenclatures.yml
	config/locales/eng/complement.yml
	config/locales/eng/nomenclatures.yml
	config/locales/fra/nomenclatures.yml
	config/locales/jpn/nomenclatures.yml
	config/locales/spa/nomenclatures.yml