* Add new 'pulumi state' command for editing state
This commit adds 'pulumi state unprotect' and 'pulumi state delete', two
commands that can be used to unprotect and delete resources from a
stack's state, respectively.
* Simplify LocateResource
* CR: Print yellow 'warning' before editing state
* Lots of CR feedback
* CR: Only delete protected resources when asked with --force
