Split up codebase into the packages @clsterio/lib, @clusterio/master,
@clusterio/slave, and @clusterio/ctl using lerna to manage them. This
will allow deployment to use only the parts needed reducing install
size, and better separate the code into shared library, master, slave
and control.
Add section to contributing guidelines detailing that single quoted
strings should not be used. The use of it has only resulted in the
addition of more inconsistency to the codebase.