Use main world after first DOM window was closed

Fix rogerwang/node-webkit#2171
check security origin when disable CSP for Node frame

Fix rogerwang/node-webkit#1672
return nullptr after accessing objects in other domain was denied

Fix rogerwang/node-webkit#1573
convert to DOM for debugging into Node scripts

Fix rogerwang/node-webkit#2214
Merge commit '5294f50e8e7dd5dae45c3e3ffd19feafcf34de92' into development10