Changes to compilation to support linux

[jakeschuurmans]

Why CGO_ENABLED=0 to support linux:

CGO_ENABLED tells Go to interoperate with C stdlibs. Its for xcompile. So it is dynamically linking the stdlibs when its started. So when we turn it off with CGO_ENABLED=0 we statically link the binary.
Alpine is very lightweight, and don't have any stdlibs at all. They are expecting a fully functional binary. So when our containers (with dynamic linked) try to run the binary, they attempt to load in the shared libs.
The problem is that on MacOS, this is by default turned off. On Linux it is on by default. So we need to turn it off.

Thats why you would get errors like this:
exec /usr/sbin/flasher: no such file or directory
Its not that the binary is missing, but that linux failed to find the shared libs it needed.

Also doing some cleanup of the makefile