Sampa compatible for espeak, and replacement of characters in fr-fr

[Rachine]

Hello,

Maybe the pull request is not fully complete, but maybe @mmmaat can start to take a look at it. Thanks

[mmmaat]

Hi @Rachine, thanks for the PR! I will look at it in detail in few days. At a first look, few suggestions:

• I don't like the idea to add a dependency to pyyaml as this is not strictly required (a space as separator in a text file is enough). Less dependency is better.
• the mapping file must go in phonemizer/share and must be loaded using pkg_resources from Python code (as for the festival script phonemize.scm for instance). This is the cross platorm way to load files in a Python package, will work on Linux/Mac/Windows with an install from sources/pip/conda/etc...
• Well... that's all :)