For each taxonomy type of productmaker, productcategory, productname, trimline,
and releasestate, the tool should be able to:
list all labels of the entries for that type
add a new entry of that type given a name and a label
update an entry of that type given a label and a name
delete an entry of that type given a label
display the details (label, name) of an entry of that type given a label

Requires:
http://brewweb.devel.redhat.com/brew/getfile?taskID=1095868&name=rhn-content-mgmt-0.4.4-1.noarch.rpm

To test:
 - As listed in comment #1, for each of the taxonomy types (maker, category, 
   name, trimline, and releasestate), you should be able to perform all actions
   (list, create, read, update, and delete).
 - Commands are of the form rhn-taxonomy ACTION TAXONOMY_TYPE <extra parameters>
   e.g. rhn-taxonomy list maker
        rhn-taxonomy read releasestate beta
 - Actions should display appropriate error messages when you try to modify or 
   view something that does not exist, or create something that already exists.
   e.g. rhn-taxonomy create maker james "James makes stuff in rhn"
   Should display an error message if there is already a maker with the label 
   'james'
  

 
 

I added text about commit in 0.4.6. Integrity constraints are trickier,
depending on when we go to qa it might not fit in.