Megatest

If i run: megatest -list-runs % -target % -fields tests:test_name,item_path

I expect to see only run and test info, not step info

When specifying -fields, step info should only be displayed when steps or +steps is specified.

The desired behavior is consistent with specifying run info in the fields - test info is suppressed then unless tests are specified

# shows runs, tests, and steps

-fields runs:runname+tests:test_name+steps:step_name

# shows runs and tests, no steps:

-fields runs:runname+tests:test_name+item_path

For script automation around -list-runs, it would also be nice if the test output looked like:

  Test: cv item_path: c/lpp

Rather than: 

  Test: cv(c/lpp)

If it needs to be handled with a different dumpmode, that is ok too

megatest -list-runs should allow listing tests without steps if specifying fields