This introduces a new content option, line_endings, which is used to

define the explicit type of line endings the content uses. This is

primarily important for diff content, due to real-world encounters with

diffs that only appear to be in one form of line ending or another.
Along with this, information on content sections now explicitly state

that the section must end in a newline in the section's encoding.

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worked correctly. Checked for spelling errors.