Modulize screen configuration retaining process

Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Calculate X axis -1 value based on screen

It didn't care user specified screen when calculate X asxis of window
with -1 value.

Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Support relative / absolute mode for arguments

Now, screen and coordinate arguments can specify self's mode, absolute
or relative.
User can adjust screen and coordinate of left, top, right, bottom of
window relative to currently active window.

Signed-off-by: SeongJae Park <sj38.park@gmail.com>