This exposes most of the `RewriterBase` methods to the C API.
This allows to manipulate both the `IRRewriter` and the
`PatternRewriter`. The
`IRRewriter` can be created from the C API, while the `PatternRewriter`
cannot.
The missing operations are the ones taking `Block::iterator` and
`Region::iterator` as
parameters, as they are not exposed by the C API yet AFAIK.
The Python bindings for these methods and classes are not implemented.
