- DNs are always used in canonical form: lowercase, no spaces. This is
  how they are internally handled and stored in paths and fields such as
  member and memberof
- Attribute names now can have any combination of lower/uppercase and
  stuff should work
- When modifying an attribute with a name that hase a different
  lower/upper combination than the previously stored value, keep the
  previous attribute name
- Trim spaces from values and do not store empty values

Following errors compiling with go 1.13
See https://blog.golang.org/migrating-to-go-modules for details.

Also add metadata fields in objects created on initialization

After an object has been updated, membership information must be
propagated to other object. Such operations may fail when calling consul
but if they do we don't return fail immediatly returning an error code
any more.  Instead we just print all the errors to our logs and try to
process the remaining updates.