Add the GitIgnore files. Remove some unused files.
Add the unit test project for the core project.
Add XML comments
Add unit test for new method
Add unit test for GetFolderName and Save methods.
Remove some unused code.
Add unit test for data package.
Fix bugs in models. Add the unit test for it.
Add the ExceptionHandling attribute to handle the exceptions.
Change the result of the rest APIs.
Merge branch 'feature/1' into develop