Revert "Merge pull request #51 from yasuoza/delaying_require_pry"

This reverts commit 95e766690f16e7d5fe500adad97c30a08c4ae91e, reversing
changes made to 8474f20704a8cc425ab18e3a3fbcd1cda0a3eda6.

This change was rendered unnecessary by v0.9.12.5 of Pry.