Add ability for multiple counters that are RESTful

As a: User
I need: the ability to create multiple RESTful counters
So that: I can keep track of multiple hit targets

Assumptions:

We will implement using REST API guidelines
Add ability to create multiple named counters
Add ability to update counters by name
Add ability to delete counters by name

Tasks:

Need to update root / URL to return json message
Need to rename /counter to /counters
Need to change GET to only return the counter
Need to implemtent POST to create new counters
Need to implement PUT to update multiple counters
Need to implement DELETE to delete multiple counters

Acceptance Criteria:

Given I have a multi-counter ability
When I create a counter named foo
And I update the counter named foo to 1
And I call the hit /counters/foo URL
Then I should see 1 returned from the service