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### Removed
- the ability to specify `&StringSlice{...string}` or `&IntSlice{...int}`.
- To migrate to the new API, you may choose to run [the migrator
- (python) script](./cli-v1-to-v2).
-- The optimistic reordering of arguments and flags introduced by
- https://github.com/urfave/cli/pull/36. This behavior only worked when
- all arguments appeared before all flags, but caused [weird issues with boolean
- flags](https://github.com/urfave/cli/issues/103) and [reordering of the
- arguments](https://github.com/urfave/cli/issues/355) when the user
- attempted to mix flags and arguments. Given the trade-offs we removed support
- for this reordering.
- adapter code for deprecated `Action` func signature
- deprecated `App.Author`, `App.Email`, and `Command.ShortName` fields
- All `Context.Global*` methods, as the non-global versions now traverse up
