Implement module `Phonon` for phonon calculation

[singularitti]

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• [ ] Tests for the changes have been added (for bug fixes / features)

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• What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)

The first try of a phonon calculation framework.

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• Does this PR introduce a breaking change? (What changes might users need to make in their application due to this PR?)

No.

• Other information:

[singularitti]

I am waiting for parse(PHononInput, read(io, String)) and parse(Q2RInput, read(io, String)) to be implemented. They should be simple. Please refer Base.parse(::Type{PWscfInput}, str::AbstractString). @searchengineorientprogramming