Fix misplaced code highlighting
Partially addresses #286 (closed) (mistaken line highlighting).
Adjusts stacktrace line highlighting to account for cases in which the context list starts at 0 instead of 1.
Edited by james kiger
Partially addresses #286 (closed) (mistaken line highlighting).
Adjusts stacktrace line highlighting to account for cases in which the context list starts at 0 instead of 1.