Combined announcer outputs binaries to stdout

[mvz]

Summary

When activating the blanket announcer with @announce, the command_content announcer announces the full binary file if the command happens to be a binary file. This is bad and shouldn't happen.

Expected Behavior

When annotating a scenario with @announce, announced output should be useful for the developer.

Current Behavior

When annotating a scenario with @announce, all announcers are activated. The command_content announcer is one of them. If the command is a binary (e.g., ruby), the full binary is output, filling the terminal with a large amount of garbage.

Possible Solutions

1. Have the command_content not output binaries.
2. Do not include command_content in the announcers activated by @announce.

I think 1. is the best option, since it also removes the need for warnings about binaries in the documentation about the command_content announcer.

Steps to Reproduce (for bugs)

1. Create a scenario annotated with @announce
2. Have the scenario run ruby --version
3. Run the scenario

Context & Motivation

This came up while examining #563, as mentioned in #649 (comment).

Your Environment

• Version used: master, maybe also still
• Operating System and version: Linux