Add options to disable external assets again

[julianstolp]

In version 2.x it was possible to disable external dependencies for offline installations. see cachethq/cachet#3210. This is no longer possible in 3.x. For offline purposes, however, this makes the application unusable.

[jbrooksuk]

I believe the only thing being loaded externally are from the dashboard which is the font. We can configure this dynamically from a setting though.

@julianstolp are you seeing any other assets / dependencies being loaded externally?

[julianstolp]

I found several external urls, most are font related

Internal Server Error Page:

• https://fonts.bunny.net/css?family=figtree:300,400,500,600
• https://fonts.bunny.net/figtree/files/figtree-latin-300-normal.woff2
• https://fonts.bunny.net/figtree/files/figtree-latin-ext-300-normal.woff2
• https://fonts.bunny.net/figtree/files/figtree-latin-400-normal.woff2
• https://fonts.bunny.net/figtree/files/figtree-latin-ext-400-normal.woff2
• https://fonts.bunny.net/figtree/files/figtree-latin-500-normal.woff2
• https://fonts.bunny.net/figtree/files/figtree-latin-ext-500-normal.woff2
• https://fonts.bunny.net/figtree/files/figtree-latin-600-normal.woff2
• https://fonts.bunny.net/figtree/files/figtree-latin-ext-600-normal.woff2

Dashboard Pages:

• https://ui-avatars.com/api/?name=a&color=FFFFFF&background=09090b
• https://fonts.cdnfonts.com/css/switzer
• https://fonts.cdnfonts.com/s/85792/Switzer-Regular.woff
• https://fonts.cdnfonts.com/s/85792/Switzer-Medium.woff
• https://fonts.cdnfonts.com/s/85792/Switzer-Semibold.woff
• https://fonts.cdnfonts.com/s/85792/Switzer-Bold.woff

Login Page:

• Same as Dashboard Pages except ui-avatars.com