Add scripts to chutney so it works on a tor binary

If chutney was self-contained and could run tests on a plain tor binary, it would be easier to do jenkins tests using chutney.

To make chutney work, we use parts of the tor git tree, including some Makefile targets to select the tests we run, and src/test/test-network.sh.

If we move these scripts to the chutney tree, we can run a set of chutney targets anywhere, without requiring a tor build tree.