Carry webhook settings forward to new workspaces

[andrewrfreed]

See #113 and #176

Upon further testing, the additional parts of the json we may want to capture for future enhancements are related to the "webhooks" section. Probably not urgent, but something for a future enhancement.

"webhooks": [
{
"url": "http://XXXXXXXX",
"name": "main_webhook",
"headers": [
{
"name": "XXXXXX",
"value": "XXXXXX"
},
{
"name": "Accept",
"value": "application/json"
}
]
}
],

[andrewrfreed]

Still seems applicable - the linked issues covered system_settings but not webhooks. This probably does not affect classification model but still means the duplicated workspace is not quite equivalent to the original workspace.