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- Added support for requirements.txt.
- Added parameters to skip executing setup.py.
- Added a setup-commands parameter to override how the virtualenv is made.
- The -e parameter now actually works.
- The information about the python execs is now cached. This speeds up
startup, a lot, fetching the Python environments goes from around 5
seconds to less than a tenth.
- A profile of each virtualenv is now saved in the virtualenv, containing
it's name, the full path of the Python exe, and the installed requirements.
A virtualenv will now only be updated if this has changed since the last run.
This also speeds up tests runs a lot in the typical case.