New folder structure proposal for syskit merge

replaces:
https://github.com/planthaber/rock-webapp/pull/8
> Why don't you require rock/webapp/syskit/api ?

Included here: https://github.com/planthaber/rock-webapp/pull/13

But still uses a root class to mount (mentioned somehwere we should keep them to be able to add api versions in future), i guess the loggers can stay there