`python -m smdebug.rules.invoke_rule` fails

[jarednielsen]

For example,

python -m smdebug.rules.rule_invoker --trial-dir ~/ts_outputs/vanishing_gradients --rule-name VanishingGradient --threshold 0.0000000001

This fails because there's no main function, and it leads to a double-import where smdebug.rules has an init.py which imports invoke_rule.

[rahul003]

This will no longer work as we have no 1p rules here anyway