Adds credential application tracker to admin console

[Lucas-Mc]

This change adds a credential application tracker to the admin console under the "Usage Stats -> Credentialing" tab. This graph tracks the number of applications submitted, subtracts the number processed, and plots that difference over time (pending applications). This graph is created with D3 SVG and is semi-dynamic given a window size where is adjusts its window size onload but not onchange. I also fixed one of the entries in the demo data which had an application date after its approval date.