Install critcl modules into subdirectories

[apnadkarni]

Currently installing critcl results in all critcl modules being installed at the top level of [info library]. Installing them under a single critcl directory would reduce a lot of clutter. On one hand this is strictly a "cosmetic" issue but on the other, I find my lib directory a bit of a mess in terms of finding other stuff after installing critcl.

Obviously not a big deal ...