minor: edits to nearSphere

Signed-off-by: Sam Kleinman <samk@10gen.com>
update css

Signed-off-by: Sam Kleinman <samk@10gen.com>
DOCS-1441 move info from footnote to table in ensureIndex

Signed-off-by: Sam Kleinman <samk@10gen.com>
reorg: cursor methods ref toc