Program & library versioning
----------------------------

Program
-------

Simple version like "1.0".

Library
-------

Using libtool convention, we define 3 numbers.

When library "natural" version is "1.0" we have:

1:0:0

When we'll release a new API, "natural" version will
be "2.0", so we'll have:

2:0:0

If we release a new implementation of this version 2.0,
without any API change, we'll have:

2:1:1



