[#681] throw an exception indicating to use JSON if XML parsing is not supported by the browser/platform
[#681] throw an exception indicating to use JSON if XML parsing is not supported by the browser/platform

funnily enough, CocoonJS now support it when using webview and webview+,
this is however still useful when using canvas+ (that does not implement
DOMParser)

gopalindians/melonJS,melonjs/melonJS,melonjs/melonJS,rlugojr/melonJS,TukekeSoft/melonJS,rlugojr/melonJS,srbala/melonJS,TukekeSoft/melonJS,gopalindians/melonJS,TukekeSoft/melonJS,gopalindians/melonJS,rlugojr/melonJS,srbala/melonJS,srbala/melonJS