chore(benchmark): remove test for generateReportPartial
feat(benchmark): add statistical functions to calculate confidence interval
feat(benchmark): add confidence and stability info to averages
feat(benchmark): calculate relative margin of error and simplify report
fix(benchmark): fix standard deviation calculation

Previous algorithm was dividing total of squares by sample length,
where it should have been dividing by sample length minus 1
feat(benchmark): add standard deviation to report
chore(benchmark): remove interpolateHtml method
chore(benchmark): remove redundant getAverages method