Support encoding in Command.Read()

[rasmus-unity]

What

Added encoding parameter to Command.Read() method

Why

We experienced when running git diff --patch on Windows, that UTF8 changes where not returned correctly, assuming since Encoding.Default on Windows doesn't support Unicode/UTF8

Tests

None, but verified all existing tests are still passing. Let me know if you think there should be tests for this

[adamralph]

@rasmus-unity thanks for raising this PR. This seems like a good addition to the API.

I need to tweak the implementation a bit, and add tests, but you haven't given me permission to push to your branch, so I'm going to close this and replace it with another PR. Your name will still appear as a co-author of the implementation commit.

[rasmus-unity]

Thanks @adamralph, appreciated that you accepted the change :)