- fix miscalculation in column numbers when multiple tabs

- fix miscalculation in column numbers when multiple tabs
  or empty lines are involved;
- change linku1() to return the head of the list (unused at the moment);
- ignore the source line number in runtests as they change with the
  source and cause mismatches in the comparison with the reference output.

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@23130 65c4cc65-6c06-0410-ace0-fbb531ad65f3