pause in make check

[Tatsuro M. <tma...@ya...>]

I have been noticed that make check at qt terminal 
on Ubuntu 18.04 on WSL(Windows Subsystem for Linux)
causes sometimes ugly plot (wrong aspect ratio in multiplot mode etcs.)

However, if I execute all.dem by hand, all graph appears correctly.
Perhaps this is timing issue.

Can I insert something like "pause" each run in make check?

Tatsuro