Did some more reorganization in support of separating out a redfsm.a library

Did some more reorganization in support of separating out a redfsm.a library
from code generation. The makeCodeGen function is now a callback which will be
executed by the redfsm.a library and implemented by the code generator
executable.

git-svn-id: http://svn.complang.org/ragel/trunk@39 052ea7fc-9027-0410-9066-f65837a77df0