Quiet failure on xSnprintf failure

[cgzones]

If xSnprintf fails, htop will exit just with a meesage: htop: Success
Maybe we should use abort or similar instead or err(1, NULL); ?

[BenBE]

Maybe reuse the SIGSEGV handler?

[BenBE]

This issue should be fixed by #204.

[cgzones]

Closed by #204