xlisp-test: load example files for tests, not in advance

[wobh]

See #63.

One solution might be adding a readtime conditional above defpackage for the dna package example files.

But it makes sense to take this opportunity to change how "xlisp-test" loads test data from example files. It should probably load the examples like test data, before the test is run, then afterwards using delete-package on the example package.

[verdammelt]

How about we have xlisp-test load the test and the example files before the test run and then cleanup both afterwards. That will keep each test run as independent as possible from each other.

[wobh]

#65

Not sure why it isn't referencing here. Also, not sure why all the previous commits I rebased seem to be coming along with it. Shouldn't be harmful, though.

http://stackoverflow.com/questions/5415560/github-pull-request-without-old-commits

[wobh]

With #65 merged, I think we can put this to bed.