As a side effect of wisdom-framework#171, wisdom/documentation has be…

…en renamed into wisdom/documentation-base

Technical reason is that maven doesn't allow two modules having the same artifactId and, as a convention, modules are named after the containing folder.
As a consequence, I had two choices :
 - rename wisdom/documentation into documentation-base
 - renamed documentation/documentation into .... what ?

I choosed the first because it's only the parent folder, and not the effective artifact which will contain browsable documentation (well, also because i had no idea of a valid name for the second one).