Changed Trove CLI list headers to match Nova CLI

Added ability to pass in header labels to print_list.
If not passed in, header lables are automatically created
from the fields by replacing '_' with spaces and capitalizing
each word.  IDs are also capitalized.  All field data is
now left-aligned, except numerics which are right-aligned.

Also changed print_dict so that all values are left-aligned.

Change-Id: I3b69dc7f92c496594cf37832f4ff98f1abdf52dd
Closes-Bug: #1272700
Fix trove CLI help UUID references

Changed all 'UUID' references in the CLI help to 'ID' to be
consistent with list/show commands.

Change-Id: I0284aaec71d31fd2d3fa277bba7d7e314127bfe3
Closes-Bug: #1316270
Added check for empty attributes in trove CLI

Validated that new attributes are passed in for
user-update-attributes.  Added unit test and changed help message.

Change-Id: I1363278912fb5ffddd2e64550dc6ba70df8a9df8
Closes-Bug: #1298760
Mark troveclient as being a universal wheel

Change-Id: I3ca8e2c9401da3ef10e243b3f22bf08b28d4a726
Merge "Fix trove CLI help UUID references"
Merge "Added check for empty attributes in trove CLI"
Merge "Changed Trove CLI list headers to match Nova CLI"
Merge "Mark troveclient as being a universal wheel"