attempt to call nil value newproxy

[spik3n]

Issue with running a build .exe because of nil value in global newproxy

Error:
line 254: attempt to call a nil valie (global newproxy)

[levno-710]

It seems, that Prometheus was build using a Lua Version > 5.1
I added a fix for newer Lua Versions in cb8bb42
This will be included in Prometheus v0.2