Build pnr nodes and pnr connections

…m Emme build files)

Transit line file mode 20 and 21 are switched

Bicounty Model 2035 Network Highway Update

Updates nodes_mtc_df to create a copy of model_node_id field as N. Updated pnr to be strings to conform to BCM coding.

Deleted 2020 network creation step.

Added Yue's clean script to add transit project cards

Bicounty 2035 hwy update

Bug fixes to the BCM script that applied 2035 project cards.

Revert changes that copies N field to model_node_id field.

Verified that it works with the 2015 scenario pickle file as well.

Changed how the project cards are applied. Instead of creating new scenario and applying all project cards at the same time, this version applies the highway project cards one after another from the list of project cards.

New notebook can create transit line file and highway network in tandem. Specifically modified for 2050 network creation.