Multisite Improvements

[patrickposner]

The current multisite integration is almost non-existent. It somehow works, but it is nowhere near usability-friendly.

The new concept:

• Offer a clear way to export sites from the network
• Give the ability to easily switch to "Generate" and "Settings" from the network
• Give the ability to copy settings from one subsite to another to speed up configuration

Screenshots:

Network:

Subsite: