logic sim prepare (test commit)
Merge remote-tracking branch 'origin/master'
Partially finish clone oa_design into design part, the problem we face is "no pin data structure info."
Solution:
First step: separate the input/output direction at oa_cell.
Second step: create all pin data structure and give it a map to hash the ptr.
Unroll cell and pin.
Before: Pin is deleted in destructor of Cell.
After: Pin is deleted in destructor of Library.
NameToPin map and Pin construction.
step 2 of Clone Cell commit