Bing layer's zoom level may be incorrect

[ahocevar]

Because the Bing layer may set its final resolutions array after it is added to the map and the map is rendered, there is a chance that, if it is a base layer, overlays won't align because they are still rendered at a different zoom level. The solution is to call map.zoomTo in the initLayer method, as soon as we have the final resolutions.

[ahocevar]

The above patch fixes the issue. It comes with comprehensive tests that show the issue. Tests pass after applying the patch. Thanks for any review.

[ahocevar]

Note that this patch also simplifies the way we set the resolutions: instead of maintaining a resolutions array, we just need the maxResolution, because we can calculate each resolution from the maxResolution: maxResolution / Math.pow(2, zoomLevel)

[tschaub]

Thanks for the continued work on this. Assuming tests pass, please commit.

[ahocevar]

r10997