Modify several tests to use test-skeleton.c

Modify several tests to use test-skeleton.c

These tests were skipped by the use-test-skeleton conversion done in
commit 29955b5d because they did not have an `int main (void)'
declaration. Instead their `main' functions were declared with arguments
(i.e. argc, argv) even though they didn't use them.

Remove these arguments and include the test skeleton in these tests.