--Changed reports code to use the LessonPlan object rather than test data Strings.

--Add validation of user inputs for all reports.
--Added validation checks for null/empty object arrays/lists.
Merge https://github.com/joshbaird/LessonPlanOrganizer

Conflicts:
	LessonPlanOrganizer/Entity/LessonPlanReport.cs
	LessonPlanOrganizer/Entity/Report.cs
	LessonPlanOrganizer/Entity/SubjectStatsReport.cs
	LessonPlanOrganizer/Entity/TestData.cs
	LessonPlanOrganizer/LessonPlanOrganizer.csproj
	LessonPlanOrganizer/UI/SubStatsReportInputForm.Designer.cs
	LessonPlanOrganizer/UI/SubStatsReportInputForm.cs
	LessonPlanOrganizer/UI/SubStatsReportInputForm.resx