controllers/MainController.js: allow ra/dec/zoom to override `place=` when using a goto hash
controllers/MainController.js: allow ra/dec/zoom to override `place=` when using a goto hash

Fixes #300.

This was the intended behavior, but the details of how the goto and
imageset-loading operations interacted meant that we needed to use another
timeout.

WorldWideTelescope/wwt-web-client,WorldWideTelescope/wwt-web-client