Add module-specific python setup to system tests

Add module-specific python setup to system tests

During the system test execution, allow use of module-specific
bootstrap() function in addition to the setup.sh script which this
function should ultimately replace.

The purpose of bootstrap() is two-fold. First, it can execute any
commands needed to create the initial conditions for the test, such as
creating key materials, manipulating files etc. Second, it should return
any test-specific template values as a dictionary. Those will be used to
render the jinja2 templates.

(cherry picked from commit 7474d3829513d90370e6792dc9ceb68a6738328c)