Add merlin6 at PSI

[superstar54]

In this PR, I added codes and computers for merlin6 at PSI. For more info on Merlin6 at PSI, please visit: https://lsm-hpce.gitpages.psi.ch/merlin6/connect-from-linux.html

Computer

• cpu
• gpu

Code

• pw-7.0-cpu
• pw-7.0-gpu
• dos-7.0-cpu
• projwfc-7.0-cpu
• pp-7.0-cpu