Avoid custom projection lookups by supporting the ability to specify proj4js definitions inside the Application Definition

[jng]

Currently, for any coordinate systems/epsg codes not known by the Proj4js library, it tries to look for a javascript file (/mapguide/fusion/lib/Proj4js/defs/EPSGXXXX.js) that probably does not exist. The javascript file if it exists, is nothing more than just a call to set the proj4 string in the Proj4js.defs global object

To avoid such lookups, we should have a new background widget (CustomProjections.js?) that takes in a set of Name/Value extension parameters which contains our custom proj4js projections. The widget's sole purpose is to populate the Proj4js.defs global object with our custom proj4js strings contained in the Application Definition document itself.

This way, we don't have to make such requests (or worse, trying to get the definition from spatialreference.org. Does it still do this?) as we are carry the custom proj4 strings inline in the Application Definition document.

[wuma]

This issue is not for EPSG only. For Projection CS, similar issue also exists. See: comment8 of ticket 434: http://trac.osgeo.org/fusion/ticket/434

[jng]

Including csmap2proj4.js in the build profile effectively fixes this as we now have all proj4 definitions that are convertible from their CS-Map equivalents.