Revert "Yet another attempt at making bundler output verbose."
Revert "Yet another attempt at making bundler output verbose."

This reverts commit 53c7cf91e0d6339fd8ed6a63412c0a9b7641aac8.

I came up with a workaround for the fatal Bundler error on Travis Ci
in Ruby 1.8.7 in [1], so this debug output is no longer needed.

[1] 66bab2a8f4e7cd8734bf88e6f32157c0d5153125

10io/mocha