English doc RSTification part 2: syntax.rst
Remove buffer column from end of some of the tables.

This compensated for a restview quirk to prevent ugly auto text
wrapping, but on Github it showed up the way that the grid expects:
as an extraneous column.  Github (and RST syntax rules) are right
on this, so remove the column.
English doc RSTification part 3: Oddly named stuff from maindir/

This leaves the faq_, script_, and syntax_ prefixed docs. Then we
move onto corefilters/ and externalfilters/.