[MERGE] knit text adding reductions

[Ian Clatworthy]

Some minor comments.

Robert Collins wrote:
         result = versionedfile.add_lines(
> -            self._new_revision_id, parents, new_lines)[0:2]
> +            self._new_revision_id, parents, new_lines,
> +            random_id=self.random_revid)[0:2]

Spacing around =.

          not present in file history.
> +
> +        :param lines: A list of lines. Each line must be a bytestring. And all
> +            of them except the last must be terminated with \n and contain no
> +            other \n's. The last line may either contain no \n's or a single
> +            terminated \n. If the lines list does meet this constraint the add
> +            routine may error or may succeed - but you will be unable to read
> +            the data back accurately. (Checking the lines have been split
> +            correctly is expensive and extermely unlikely to catch bugs so it
> +            is not done at runtime.)

Spelling of extremely.

Ian C.