Add support for \input command

[#73664936]
Remove puts

[Delivers #73664936]
Issue pull request for branch 73664936-input

[Delivers #73664936](https://www.pivotaltracker.com/story/show/73664936)
[Delivers #70812746](https://www.pivotaltracker.com/story/show/70812746)
[Delivers #70476292](https://www.pivotaltracker.com/story/show/70476292)
[Delivers #68462524](https://www.pivotaltracker.com/story/show/68462524)
Merge pull request #105 from softcover/73664936-input

73664936 input