GeoRSS layer does not use OpenLayers.Popup.WIDTH and HEIGHT for popups

[openlayers]

GeoRSS layers specify a hardcoded width and height for the markers' popups. It would be preferable if it would use OpenLayers.Popup.WIDTH and OpenLayers.Popup.HEIGHT instead, which would allow the popup sizes to be configured via these constants.

The path is in Layers/GeoRSS.js around line 146. Simply replace data.popupSize with this:

data.popupSize = new OpenLayers.Size(OpenLayers.Popup.WIDTH,OpenLayers.Popup.HEIGHT);

[crschmidt]

The problem with OpenLayers.Popup.WIDTH/HEIGHT is that they're global -- and that means you can't specify different ones for different layers.

Instead, add popupSize APIProperty, which, if exists, will be used to override the default Popup size of 250, 120.

(The default stays, because it was optimized for GeoRSS to begin with.)

Please review.

[tschaub]

Nicely done again. Please commit. (All tests pass in IE/FF.)

[crschmidt]

(In [4041]) add support for specifying the GeoRSS popup size as an option to the layer. Default behavior stays the same, but you can now specify popupSize as a layer option to the GeoRSS constructor. (Closes #883)