title: Is there a way to specify where raco should install a package?
body: <p>Many languages' package management systems install third-party packages in a subfolder of a given project's root repository. (E.g. <code>node_modules/</code>, <code>deps/</code>, etc.) This is nice as it allows multiple versions of a single package to coexist nicely, as each is isolated to the project that depends on it.</p>
  
  <p><code>raco</code> by default installs packages system-wide it seems. Is there a way to tell <code>raco</code> it should install packages in a particular folder?</p>