[Cellular Library] Align folder structure with other library.

[andysun2015]

Description of changes:

• Align folder structure with other library.

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[paulbartell]

Some of your makefiles are missing new lines at the end of the file. This is generally good practice.

I would also suggest adding a .gitattributes file so that contributors on windows platforms will commit "\n" line endings rather than "\r\n".

https://docs.github.com/en/get-started/getting-started-with-git/configuring-git-to-handle-line-endings

[andysun2015]

Some of your makefiles are missing new lines at the end of the file. This is generally good practice.

I would also suggest adding a .gitattributes file so that contributors on windows platforms will commit "\n" line endings rather than "\r\n".

https://docs.github.com/en/get-started/getting-started-with-git/configuring-git-to-handle-line-endings

I've added the .gitattributes file for line ending correction.
Please refer to this commit.