Work out how to host docs for individual tools

Ideally we want:
a) Tool-specific docs to be part of the relevant repo so that docs can be updated along with code (and autogenerated API docs)
b) All docs to be accessible via one site (brainglobe.info)

How do we do this? I haven't found any tool to automate this, the best way seems to be some kind of custom build script. The process could be something like:
* Include docs in all repos
* Have a central repo (this one) which contains general BrainGlobe info, and a script to:
* Find all repos with docs
* Copy files
* Build one large site with all appropriate links

Any ideas @alessandrofelder? We should think about this as we start to accumulate more documentation for different parts of the project.

Start in this central repository and review how documentation is currently hosted. Investigate the documentation in individual tool repositories and the proposed process for finding repositories, copying files, and building one site at brainglobe.info. Done means tool-specific and general docs are available through one site with appropriate links.

Written by the indexing model from the issue text.