A bounds checking bug allows the X in -LX to extend one line past the
end of file. For example, given a file with 5 lines, -L6 is accepted as
valid. Demonstrate this problem.
While here, also add tests to check that the remaining cases of X and Y
in -LX,Y are handled correctly at and in the vicinity of end-of-file.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>