Merge pull request #549 from dbetebenner/master

Pushing major update of student growth plot to master together with other updates (JSON export)
Merge pull request #550 from dbetebenner/master

Update of studentGrowthPlot interpolation
Merge pull request #551 from dbetebenner/master

Minor updates for CRAN pass
Merge pull request #552 from dbetebenner/master

Update of date and incorporation of toy examples
Merge pull request #553 from dbetebenner/master

Update to 1.2-1.0 and change of example from studentGrowthPercentiles to...