This wont compile. Dont bother trying.
The only interesting stuff is in boid.h
There is some std vector dodgyness, and the whole thing isn't really a good example of how one should be coding. Anyway, it might help clear up whats going on. There isn't any rocket science. 
It would be nice if you credit me if you use the code or ideas though.

Update: Extra files included where I attempted acceleration control