Support i18n within all directories supported by jsonConfig

Upcoming admin will support location of i18n files in directories withput naming restriction to i18n., i.e. admin/myI18n

See https://github.com/ioBroker/ioBroker.admin/tree/add-objects-from-text/packages/jsonConfig#translation-in-separated-files-compatible-with-weblate

Checker should support / check files located there too.
