AspNetCoreModule should set content type when serving app_offline.htm

[moozzyk]

Currently when AspNetCoreModule does not set content type at all when serving app_offline.htm which can result in this: https://cloud.githubusercontent.com/assets/1438884/15302651/ec3c58d6-1b68-11e6-9f26-a28fee642c7e.png

[muratg]

@pan-wang Could you have a look?

Also, maybe someone from WebDeploy team should look into default app_offline.html file... I'm not convinced it should have an xml tag.

@sayedihashimi Could you cc WebDeploy engineer?

[moozzyk]

There is already an item for this: https://github.com/aspnet/Tooling-Internal/issues/576

[pan-wang]

this will be fixed in next release

[Tratcher]

@pan-wang please add the Done label to issues when you've checked in the fix. We'll plan to verify and close them.

[pan-wang]

this has been fixed and will be included in next release