Use https, not svn to check out the ptII repository
In April, 2010, we discussed using https to check out the ptII tree instead of using the svn protocol.
The primary reason to use https instead of svn is that https is more likely to
get through corporate firewalls.
One reason not do use https is because there are very few https accounts
with write privileges on source.eecs.berkeley.edu. Switching to https will
make it more difficult for Kepler developers to contribute fixes to ptII.