Merge admin/common exim templates

As with any time I touch exim, I have complete confidence that this is
broken in some way I do not understand. You're Welcome.

Fixes rcbops-cookbooks/swift-private-cloud#70
Merge pull request #182 from claco/issue-70

Merged automatically by jenkins after successful build test
Refactored the common includes

External recipes that should be used are:

* account-server
* object-server
* container-server
* admin-server
* proxy-server

All the rest should not need to be used externally.

closes #72 (ish)
Fix cron user

No need for this to be swiftops.  Could just as easily be any
user.
Fix owner and perms on drive check

No need for this to be secret to swiftops.  :(
Merge pull request #185 from rpedde-rcbops/issue-72

Merged automatically by jenkins after successful build test