* grep_proc.cc: When a request is queued with the start line
== -1, we need to start searching from the highest line
ever seen and not the last line processed.
* line_buffer.cc: If a partial line was read, we need to
avoid returning another line if more data is appended
to the file.
* lnav.cc: Accept file name patterns on the command-line that
don't match any files yet. Initialize the screen before
redirecting stderr to the log file or /dev/null.
* log_format.hh: Add some comments. Start to add back support
for scrubbing.
* logfile_sub_source.cc: Move scrubbing to the format impl.
* textview_curses.hh: Add comments.
