array-to-string-transformer
``` [1,2,3,4,5,6,7,8] -> "1-8" [1,3,4,5,6,7,8] -> "1,3-8" [1,3,4,5,6,7,8,10,11,12] -> "1,3-8,10-12" [1,2,3] -> "1-3" [1,2] -> "1,2" [1,2,4] -> "1,2,4" [1,2,4,5,6] -> "1,2,4-6" [1,2,3,7,8,9,15,17,19,20,21] -> "1-3,7-9,15,17,19-21" [1,2,3,4,5,6,100,1091,199
