Curator stackage build with stack

[qrilka]

Please include the following checklist in your PR:

• Any changes that could be relevant to users have been recorded in the ChangeLog.md
• The documentation has been updated, if necessary.

Tested using the latest Stackage snapshot builds.

Fixes #4217

This mostly changes curator code but also adds extra tweaks into Stack's code to deal properly with expected test and benchmark failures

[qrilka]

The last rebuild took

real    3m14.387s
user    1m5.144s
sys     0m9.860s

so it looks more or less OK and #4550 should improve it a bit more

[snoyberg]

I've looked this over and discussed with @qrilka. This all looks good to me. Only concern is whether mutable packages trigger rebuilds appropriately. Recommendation: add an integration test that works as following:

• Mutable, local copy of a package like filepath in extra-deps
• Single local package that depends on a package in the snapshot which uses filepath
• Perform a non-profiling build
• Perform a profiling build

This will necessitate rebuilding all three packages (filepath, the one depending on it, and the local package). If this works, then we're good.

[qrilka]

@snoyberg looks like I found a problem which is a bit related to removing of InstalledCache but it's not about mutable dependencies (it looks to be that we shouldn't have problems specific to them). When we switch between different implicit snapshots (e.g. by adding --profile) we could loose information about dirtiness of local files and we have a following failure scenario:

1. You have package compiled with and without profiling
2. You change some files in that package
3. You build it without profiling
4. Then when you build it with profiling there's no information about dirty files so you have Stack's build results for files you had in 1)

I will work on fixing this (and will add a test for that of course)

[qrilka]

Fixed rebuilds and added 2 integration tests