[FEATURE] Grouped variable declaration

[divshekhar]

Description

// Declaration
var (a,b,c);

// Initialization with one value
var (
    a,b,c = 10
);

// Initialization with multiple values
var (
    a = 0,
    b = 1,
    c = -1,
);

With Datatypes:

// Declaration
var (a,b,c): int;

// Initialization with one value
var (
    a,b,c: int = 10
);

// Initialization with multiple values
var (
    a: int = 0,
    b: bool = false,
    c: string = "hello",
);