Make `undefined_module` error contain module name

[horkhe]

I got a complain from my colleague that undefined_module error does not tell what particular module was undefined. This pull requests addresses that deficiency.

Besides it brings some empty line cleanup.

So only the first commit, which is really small, contains code changes. The second just removes extra empty lines.

[horkhe]

Interesting, the build broke for R14B03 only. It looks like a glitch in an Erlang node that was running the build.

[eproxus]

:+1: Merged.