A series of minor updates / cleanups

[jsquyres]

Several commits for trivial cleanups (reviewers are strongly encouraged to look at commits individually rather than the entire PR diff):

• contrib/spread: remove old/unused contrib sample script
• ompi-spec-generator.py: updates for Python 3
• trivial: mark a bunch of files executable that are actually executable
• trivial: remove executable bit from this file; it's not executable
• trivial: remove blank lines at end of files
• trivial: trim trailing whitespace from lines

The last 2 commits are possibly the only controversial ones. They're arguably cleanups, but related to style. They do make trivial whitespace changes to several lines in the middle of files.

[bosilca]

Personally, I don't see any interest in touching other people code just to remove a trailing empty line. Is there any technical reason for this?

[jsquyres]

Is there any technical reason for this?

No, there's no technical reason for the 2 style-related commits. I had the hood up (so to speak) while working on another PR, and I accidentally ran a tool of mine that "fixed" all the whitespace problems. So I figured I'd include those changes here to see if there was any interest in including them. They're trivial, but I do agree that they are style changes.

The first 3 commits on this PR do have technical justifications, though.

[bosilca]

I have no concerns about the technical commits, just the change of style. Too invasive for no apparent benefit.

[jsquyres]

I have no concerns about the technical commits, just the change of style. Too invasive for no apparent benefit.

Ok, I removed the last 2 (style-related) commits. If you're cool with this, please approve the PR. Thanks!