Missing ldflags parameter

[Kroustille]

At this moment, godog doesn't support ldflags feature like go build or run commands.

If the application needs to use an external library already compiled, that need to be linked to the application, it's not possible.

The usage of the ldflags flag throws this error:
flag provided but not defined: -ldflags

[l3pp4rd]

Hi, yes, at the moment, godog binary does not provide build flags, duplicate of #154 this is going to be implemented someday later, for now I suggest to integrate godog within go test command using TestMain as described in the readme.