Systemd init support for loading cache volumes

[mbdebian]

Hi guys, I just wrote a few files to support Systemd init system.
I've tested this on a Debian 8.4.
I still have to solve a little issue with flashcache sysctl volumes parameters, not being applied when loading the volumes, probably because procps gets executed too early, but that will be an easy extension of the flashcache_loader script
This software is great fulfilling its goal, specially for absorbing burst writes to a slow backend like the Seagate Archive drives.
Thanks,
Manuel

[ghost]

Thank you for your pull request and welcome to our community. We require contributors to sign our Contributor License Agreement, and we don't seem to have you on file. In order for us to review and merge your code, please sign up at https://code.facebook.com/cla - and if you have received this in error or have any questions, please drop us a line at cla@fb.com. Thanks!

[ghost]

Thank you for signing our Contributor License Agreement. We can now accept your code for this (and any) Facebook open source project. Thanks!

[mbdebian]

A few more additions

[mbdebian]

The configuration files now go in /etc/flashcache, and I extended the helper script to apply sysctl flashcache properties for the loaded volumes.

[jkkm]

sorry for the lack of any response. i'll take a look at this before the end of the week. thanks for your contributions!