Add tagging data to summary functions

[florianm]

Refactor functions from the new combined tagging and track census report:

• Use wastd_data as first param which contains track and any imported tagging data.
• Use optional param w2=NULL. If NULL, use any tagging data from wastd_data, if given, expect wamtram_data and extract tagging data from there.
• Be robust against no tagging data present in either wastd_data or wamtram_data for places with track census only.