Switch testing dependencies to libtap++ and get tests at least building again.
Add regression and performance tests for line_to in preperation for testing a new line_to implementation.
Merge branch 'fix-testing' of https://github.com/kevingranade/Cataclysm-DDA into kevingranade-fix-testing
Merge branch 'master' of https://github.com/CleverRaven/Cataclysm-DDA