Add version 1.3.94 ebuild, upgrade supported EAPI, to version 5, in all ...

Horea,

Is this pull request OK? I've left in the old btsync versions. They are however all updated to the new ebuild - the manifest builds - so the SRC URI's must still be OK.

I've spent a very long time getting familiar with systemd. I really don't have a clue about OpenRC - so it would be really hard for me to say if the init daemon script will work or not (it was pulled from a Gentoo overlay many months ago).

Robert