SLIB entry in module list appears out of date - might need 3b4

[Max Arai (developer)]

The module reference in https://raw.github.com/jralls/gnucash-on-osx/master/modulesets/gnucash.modules to slib appears to be out of date.

The current release is 3b4.  The 3b3 zip file is no longer located at http://groups.csail.mit.edu/mac/ftpdir/scm/slib-3b3.zip

Instead, only http://groups.csail.mit.edu/mac/ftpdir/scm/slib-3b4.zip is available and allows the gnu cash build to complete (2.4 on OSX 10.8).  I'm uncertain how to test this.

Cheers,
Max