Replace CR characters with newlines

[jboynes]

Replaces standalone \r characters in these files with \n for consistency across the codebase.

[coveralls]

Coverage remained the same at 64.71% when pulling 3d83517 on jboynes:no_returns into 0cd6f98 on GoogleCloudPlatform:master.

[aozarov]

Looks good. To avoid future variant line-ending do you mind to include a .gitattributes (with text eol=lf) in this PR to force Unix line ending (see this).

[jgeewax]

+1 to that idea @aozarov

[jboynes]

I don't mind but would point out that most[1] other projects don't have a per-repo attributes file - they leave it to the user to set the options in their git client.

[1] I checked the first five from GoogleCloudPlatform plus this is the norm on all other OSS projects I've work on.

[aozarov]

If we care about unix line ending style than I am not sure I see any wrong in doing that (and can only see the advantage of not needing any further PRs like this one). Do you?

[jgeewax]

I honestly didn't know that this was an option.... Had I known, I certainly would have encouraged it's use in the other gcloud-* repositories.....

In other words: we're saying "this repo only wants LF, not CRLF" -- sounds like a repo-specific thing, right?

[jboynes]

AIUI, this does not affect what is stored in the repo. text eol=lf means that when you checkout a file the line endings are converted to LF even on Windows. This can cause issues with some native editors, Notepad curse you ... It would be worth investigating how non-default behaviours affect various platforms - I opened #95 for that.

Whatever the outcome there we need to fix the file content in the repo. Can we pull this to do that?