numpy/numpy — pull request #431 by njsmith (2012-09-07 10:00:09+00:00)
Title: FIX: use py24-compatible version of virtualenv on Travis

Travis recently upgraded to virtualenv 1.8, which has dropped support
for Python 2.4. So, in our Python 2.4 setup script, we need to
explicitly fetch and use virtualenv 1.7.

File imported from the already-fixed version for patsy:
https://github.com/pydata/patsy/blob/ed4073adaf88463b67a1c1e2b0f02aa1eba2b944/.travis-make-py24-virtualenv.sh