Include creation date in model metadata

Introduce getter for new object "date" in ModelMetadataJSO, which
captures the return from the "models/open" API call.

Also include new test in ModelMetadataJSOTest.
Display alert when model successfully deleted
Don't allow model to be saved with an existing name

An alert is shown, asking the user to use a different name for the
model.

This fixes #81 in csdms/wmt.
Build Open droplist with populateMenu method

Instead of mechanically building the menu from all the available model
names. This sets the stage for subsetting on models that are owned by
the current user.
Don't allow duplicate model name on "Save As"

This is a follow-on to commit fcd082711ef2272a7a153b889321f4ce0944dcca.
Refactor ModelActionPanelSaveHandler#onClick

Update comments and try to make the code clearer.
Exclude test directories from wmt.war

Also:

* Lowercase the name of the war file
* Include war file in clean rule
Add unit test for ConfigurationJSO
Remove obsolete ModelListJSO#setName
Streamline storage of data from "models/list"

Store only the ModelJSO returned from the call to "models/list" in
DataManager. This will allow one API to access not only "name" and
"id", but also "owner" and "date". Prior to this, individual variables,
holding the lists of names and ids, were used. This wouldn't scale well.
Add ModelListJSO methods to get owner and date

Also add unit tests for these methods.
Only allow users to delete models they own

This is a client-side fix to https://github.com/csdms/wmt/issues/77,
which will likely be left open and reclassified as a "feature."
Serious improvements to "open model" experience

Now, only models belonging to the current user are displayed by
default. Much work was also done to streamline the code to make it
easier to follow. And to make it work correctly.
Use String#equals to match model name

Instead of String#matches, which is overly zealous in excluding matches.
Code maintenance

Clean up code; prune obsolete code; reorder packages.
Suppress the username label in Manage and Save menus

The username label for the current user must be associated with a model
when saving it. If the label isn't shown, it can't be deselected.
Merge pull request #40 from mdpiper/master

Improvements to model access and label system