Fix Arg.all() after #30 + add more tests + small refactor - #43

Hi @ffMathy ;)

Today I've noticed that after #30 Arg.all() stops working when number of arguments is greater than 1.

--for(var i=0;i<Math.min(b.length, a.length);i++) {
++for(var i=0;i<Math.max(b.length, a.length);i++) {

For e.g. [Arg.all()] and [1,2] second iteration returns false.
With min is also not correct because [1,2] and [1,2,3] return true.

I've added

    if (a.find(x => x instanceof AllArguments) || b.find(b => b instanceof AllArguments)) {
        return true;
    }

in areArgumentArraysEqual

Rest changes:

• more tests
• small refactor

I hope you will enjoy it ;)

Regards!

CC: @domasx2