fix(dictionary): avoid overwrite corruption if filenames are the same

[YodaEmbedding]

Fixes #14.

---

Consider:

function M.update_dictionary_files(dictionaries)
	for lang, dict in pairs(dictionaries) do
		M.write(filename, table.concat(dict, "\n") .. "\n")
	end
end

This leads to file corruption if filenames are identical for different langs. For instance, lang = en-US and lang = en-GB will both write to a file named en.utf-8.add.

Also, while we're at it, let's also write the output in a deterministic order for people (like me) who save their dictionaries in version control:

table.sort(merged_list)