Remove array prototype

[Ratismal]

You have created an array prototype method top. There is little point to this method.

if (!Array.prototype.top) {
    Array.prototype.top = function top() {
        return this[this.length - 1];
    };
}

You really do not need to make an array prototype to simply return the last element of an array. By doing this, you break features such as for...in.

There is debate as to whether this is bad practice or not, and I honestly don't care what you do in your own personal workspaces. However, as a public library you are unwittingly breaking other people's projects. Imagine, if you will, somebody adding this as a dependency to their large project. Suddenly, because of the array prototype, it ceases to function. Is saving 26 characters really worth this?