Allow new line characters in nbt

At the moment, when summon with nbt everything need to be on one line even in a function file:

summon minecraft:armor_stand ~ ~ ~ {CustomName:"\"MyArnorStand\"", Invulnerable: 1b, NoGravity: 1b, Invisible: 0b}

It would improve the readability if we allow new line in nbt:

summon minecraft:armor_stand ~ ~ ~ {

   CustomName:"\"MyArnorStand\"",

   Invulnerable: 1b,

   NoGravity: 1b,

   Invisible: 1b

}