Adding Get & Drop for file commands

[Manukapp]

For simple getting or dropping a single file, add get & drop to file command list.

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[codecov-commenter]

Codecov Report

Base: 56.93% // Head: 56.93% // No change to project coverage :thumbsup:

Coverage data is based on head (ecb1d69) compared to base (4fbeb3c). Patch has no changes to coverable lines.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #154 +/- ## ======================================= Coverage 56.93% 56.93% ======================================= Files 32 32 Lines 1391 1391 ======================================= Hits 792 792 Misses 599 599 ``` | [Impacted Files](https://codecov.io/gh/datalad/datalad-gooey/pull/154?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=datalad) | Coverage Δ | | |---|---|---| | [datalad\_gooey/simplified\_api.py](https://codecov.io/gh/datalad/datalad-gooey/pull/154/diff?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=datalad#diff-ZGF0YWxhZF9nb29leS9zaW1wbGlmaWVkX2FwaS5weQ==) | `100.00% <ø> (ø)` | | Help us with your feedback. Take ten seconds to tell us [how you rate us](https://about.codecov.io/nps?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=datalad). Have a feature suggestion? [Share it here.](https://app.codecov.io/gh/feedback/?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=datalad)

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[mih]

Crippled FS failure is unrelated

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