suggest to change json file check in ccs._load function

[jaunusa]

Hi

For my web export I modify the paths to achieve versioning for loaded resources:

"res/MyNode.json" to "res/MyNode.json?v=1.5.2"

But the check for json files fails because the ending is "json?v=1.5.2". I suggest to change the extension check (line 41) from:

if(ext !== "json" && ext !== "exportjson")

to:

if(ext.substr(0, 4) !== "json" && ext.substr(0, 10) !== "exportjson")