Fix 10gbe tuning for system not supporting /etc/sysctl.d/

- removes unneeded tuning parameter fs.file-max (see commit message)
- do not create  /etc/sysctl.d/ as that break the kernel-panic recipe in barclamp-crowbar
- try to reload sysctl settings if needed on systems that to not read  /etc/sysctl.d/*  when boot