Design platform instrumentation

[craig-willis]

Per the proposal:

"In addition to specific course-based evaluations, general usage analytics will also be conducted for the platform. While traditional usage geographic distribution and counts for individual applications can be collected using tools such as Google Analytics, we will also instrument our platform to collect data on complex usage patterns such as application usage chains. Such information can be used in recommending applications for users. Application specific instrumentation will also be added for contributions from project members. We will explore integrating progress tracking within the Jupyter instructional notebook to analyze the effectiveness of this instruction method."

At a minimum, this should include per-application usage information.