Improve documentation on how to install contributions

[jubianchi]

Contributions are being added to the hoathis/ namespace. They are a kind of library which is really different from Hoa native libraries: sometime they won't follow the same rules when it comes to install them.

I propose to add a section in http://hoa-project.net/Source.html to explain those difference and give some directions to the end-user.

See hoaproject/Contributions-Symfony-ConsoleBundle#8 (comment)

[Hywan]

Is still opened?

[jubianchi]

@Hywan i think nothing has been done pn the official doc aboit contributions so I would say that this issue is still open ;)

[Hywan]

@jubianchi Nothing has been done but here are my thoughts. Since we are talking about contributions to other projects, installations are really dependent of the targeted projects. So it might be part of the README to explain how to install instead of the “Source page”. Thoughts?

[Hywan]

ping?