Allow passing of origin param

[rlach]

At this line https://github.com/spencermountain/wtf_wikipedia/blob/7f08539402dd9dd2a154a591932ba91b2decbdeb/src/_fetch/makeUrl.js#L11

you set origin to * and this cannot be changed anywhere. Due to how pages are configured we need to pass proper origin both in Origin header and origin parameter - and those have to match. It would be great if wtf_wikipedia had .fetch parameter to overwrite this.

[wvanderp]

Would it be enough to set the origin parm equal to the header if provided? Or does it need to be changed independently?

[rlach]

For my needs it can be changed together.