Do not depend on require-module

Previously dsm unilaterally depended on org.tfeb.tools.require-module. This in turn caused some of the org.tfeb.hax to be compiled with that loaded, which then broke quicklisp builds when those compiled files got reloaded without org.tfeb.tools.require-module loaded. I don't want to make org.tfeb.hax depend on org.tfeb.tools.require-module, so I've made dsm not depend on it unilaterally.

That's the only change: there's no change to how dsm works.