Feature request: Allow multiline command invocation

[AgainPsychoX]

Feature request: Allow multiline command invocation for improved readiblity.

Motivation example

/summon minecraft:chest_minecart ~ ~ ~ {CustomDisplayTile:1b,DisplayOffset:6,Tags:["{?furnace_minecrat_tag}"],CustomName:'{?furnace_minecart_name_json}',DisplayState:{Name:"minecraft:furnace"}}

Expected

/summon minecraft:chest_minecart ~ ~ ~ {
    CustomDisplayTile: 1b,
    DisplayOffset: 6,
    Tags: ["{?furnace_minecrat_tag}"],
    CustomName:'{?furnace_minecart_name_json}',
    DisplayState:{Name:"minecraft:furnace"}
}

Or maybe at least for now allow to end line with \ to escape new line, so following works:

/summon minecraft:chest_minecart ~ ~ ~ {          \
    CustomDisplayTile: 1b,                        \
    DisplayOffset: 6,                             \
    Tags: ["{?furnace_minecrat_tag}"],            \
    CustomName:'{?furnace_minecart_name_json}',   \
    DisplayState:{Name:"minecraft:furnace"}       \
}