3 dev functions (#11)

* Import, Export, and Upgrade Solution Functions

* Import and Export Assembly, Translations, and WebResources Functions

* Import and Export File and Image Column content Functions

* Publish Customizations Function

* Remove Register and Unregister Plugin functions. Are covered by PRT.

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Co-authored-by: Arjan Meskers <[email protected]>

v0.5.0 (#1)

Release v0.4.0