The doctests that check errors in
tests/gmpy_test_rnd.py fail with Python 2.4, as the
'File ...' line between the 'Traceback' and '..Error:'
lines is not idented. While these pass for Pythons <
2.4, they don't in 2.4. This patch fixes that.
Note that one test still fails, as the error message
given by 2.4 is slightly different (that's the problem
with using doctest, I guess).