Use . to activate virtualenv, since sh is not bash on FreeBSD.
FIX: cannot access _sqlite3.so in virtualenv on FreeBSD.

It looks like the sqlite3 module in FreeBSD cannot be *brought* to virtualenv,
since by default it is not available unless we install it from ports:

	cd /usr/ports/databases/py-sqlite3; make install;

To fix, we add --system-site-packages when creating virtualenv.