py-up fixed

Minor API change:
- If inside a delimited form --string or list-- go to it's beginning
- If not at beginning of a statement or block, go to it's beginning
- If at beginning of a statement or block, go to beginning one level above of compound statement or definition at point.
py-down fixed

Minor API change:
- Go to beginning of one level below of compound statement or definition at point.
- If no statement or block below, but a delimited form --string or list-- go to it's beginning.
- Repeated call from there will behave like down-list.