Backport 124059 from trunk.

in the download module, fixed the handling of directories that are pointed to by file-system paths and URLs

make a branch for 1.4 so that a 1.4.4 "emergency aspirin" release can be made for easy use in case the 1.5.0b3 release causes problems for someone.

adjusted testselectingpython.py the same way as easyinstall.txt earlier: there's no call to _get_dist() for setuptools anymore as we already have it

Adjusted the test so that it also works when you're testing with an older setuptools version and there's a new one on pypi.
In that case, the _call_easy_install call will really try to install setuptools first and execute other code paths than the test cares for.
A cleaner way does not seem possible as the easy_install code is really intertwined.

Merged -r105475:105584 svn+ssh://reinout@svn.zope.org/repos/main/zc.buildout/branches/reinout_distribute_upgrade_check
This is the fix for an infinite recursion when updating Distribute.
Solved by using the available setuptools/distribute for easy_installing the Distribute tgz instead of searching for it, which tries to install, which searches...

Revert to old style path.

- Incrementing didn't work properly when extending multiple files.
  https://bugs.launchpad.net/zc.buildout/+bug/421022

windows, urllib raises an invalid ioerror.

windows, urllib raises an invalid ioerror.