Multi-tenancy works

TODO backwards compatibility, mostly 'admit' parsing.

Added admitkeys, denykeys server access_rules attributes.

Various changes in access_rules building in cf-serverd

Change DeleteAuthList() to be non-recursive, also add asserts to verify
list's consistency before freeing.

In Auth type, rename "accesslist" to "accessIPs" and add "accessIDs"
which will contain the new key-based access controls. Add this new field
to Summarize().

Consolidated repeated Auth list building code into a couple of
functions: GetOrCreateAuth() and AddAccessConstraintsToAuth().

almost there WARNING DOES NOT COMPILE

strlist bugfixes and tests.

Enable source file to be a relative path in files copy_from promises.
Delete relevant acceptance test.