[Review - 1] FileSystem: Init Folder and File Structures

[satviksr]

Implement the main File System structures.

Some APIs are very similar in file and folder. Therefore created VbaFileSystemEntity as the base class for VbaFile and VbaFolder. Objects of VbaFile and VbaFolder are not to be instantiated by the user. They should be instantiated only by the FileSystem class.

Documentation can be found here: https://github.com/googleinterns/filesystem-in-appsscript/blob/master/docs/FileSystem.md

• [x] Created File and Folder Structures

Implemented Properties for File and Folder:

• [x] getDateCreated
• [x] getDateLastAccessed
• [x] getFiles
• [x] name
• [x] getParentFolder
• [x] getPath
• [x] getSize
• [x] getSubFolders
• [x] getType
• [x] isRootFolder

Testing:

• [x] File Tests
• [x] Folder Tests

[todo[bot]]

VbaFolder.getFiles - Return VbaCollection of files

https://github.com/googleinterns/filesystem-in-appsscript/blob/d8aeef2609831ef73ef1ed4cae2ef43b5073f285/FileSystem/VbaFileSystemClasses.js#L173-L178

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This comment was generated by todo based on a todo comment in d8aeef2609831ef73ef1ed4cae2ef43b5073f285 in #45. cc @googleinterns.

[todo[bot]]

VbaFolder.getSubFolders - Return VbaCollection of folders

https://github.com/googleinterns/filesystem-in-appsscript/blob/d8aeef2609831ef73ef1ed4cae2ef43b5073f285/FileSystem/VbaFileSystemClasses.js#L189-L194

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This comment was generated by todo based on a todo comment in d8aeef2609831ef73ef1ed4cae2ef43b5073f285 in #45. cc @googleinterns.