remove statging data
add TimeFilter to filter out staging records
point SynapseClient to prod
add test cases for quiz metrics
add test for TimeFilter
make the private var final
Merge pull request #69 from kimyen/develop

Eliminate staging records
fix bug - when the entity ID is not specified there should not be any
data
Revert "fix bug - when the entity ID is not specified there should not be any"

This reverts commit e4fee7166e65108933732feb2733595ec23da764.
add cache
Merge pull request #71 from kimyen/develop

Add cache
Clear cache to fix test failures.
Merge pull request #72 from eric-wu/upgrade

Clear cache to fix test failures.
Merge master to perf.