Replace sprintf with snprintf

[mrotteveel]

Replaces occurrence of sprintf with snprintf; I ignored all code in extern (including cloop). I also did not touch the .c, and .e code in examples.

[mrotteveel]

If this isn't the right time to do this, or if it should be done more incrementally instead of big bang, let me know.

[dyemanov]

And please resolve the conflicts.

[mrotteveel]

And please resolve the conflicts.

Done

[mrotteveel]

@dyemanov @hvlad Can I merge this?

[hvlad]

@dyemanov @hvlad Can I merge this?

No objection and thanks!

[mrotteveel]

@dyemanov Merging fine with you too?

[dyemanov]

@dyemanov Merging fine with you too?

Yep, go ahead.