Move sup files from supervisor to modules

[cejkato2]

According to the mailing list (the following messages), sup files will be moved from the Nemea-Supervisor repo into this repo.

https://random.cesnet.cz/pipermail/nemea/2016-November/000016.html
https://random.cesnet.cz/pipermail/nemea/2016-November/000017.html
https://random.cesnet.cz/pipermail/nemea/2016-November/000018.html

A macro NEMEASUPDIR must be defined to specify default path for installation of the sup files.

@thorgrin suggested to use /etc/nemea/sup-available/ as a default value for NEMEASUPDIR.