* **incompabile changes**
The following changes break the compatibility with previous versions
of phonemizer (0.X.Y):
* command-line `phonemize` program: new `--backend
<espeak|festival|segments>` option, default language is now
*espeak en-us* (was *festival en-us*),
* it is now illegal to have the same separator at different levels
(for instance a space for both word and phone),
* from Python, must import the phonemize function as `from
phonemizer.phonemize import phonemize`, was `from phonemizer
import phonemize`.
* New backend [segments](https://github.com/cldf/segments) for
phonemization based on grapheme-to-phoneme mappings.
* Major refactoring of the backends implementation and separators (as
Python classes).
* Input to phonemizer now supports utf8.
* Better handling of errors (display of a meaningful message).
* Fixed a bug in fetching espeak version on macos, see
[14](https://github.com/bootphon/phonemizer/issues/14).