bug fix: target lines were not updating when pft was being changed.
bug fix: target lines were not updating when pft was being changed.

refactors target line drawing to a fucntion, adds function to clear
target lines based on line style.

tobeycarman/dvm-dos-tem,tobeycarman/dvm-dos-tem,tobeycarman/dvm-dos-tem,tobeycarman/dvm-dos-tem,tobeycarman/dvm-dos-tem,tobeycarman/dvm-dos-tem