Fix argument tokenization

[matthiasbeyer]

The single and double quotes used to group words into a single command line argument must be trimmed from the tokens.

E.g. the argument of cmd "foo bar" is the string "foo bar" and not "\"foo bar\"".

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Tests locally do not run for this, but lets see what CI tells us. Maybe my setup is bogus.

Closes #39

[matthiasbeyer]

Nice, so it was indeed my local setup that made the tests confused. I guess we can

bors merge

@didier-wenzek thanks for contributing to this crate.

[bors[bot]]

Build succeeded:

• CI