correction to platform support
DOCS-1257: enterprise correction
add 2.4 to reference page

Signed-off-by: Sam Kleinman <samk@10gen.com>
DOCS-1257 changes for mongodb enterprise
DOCS-1257 fixed missing enterprise documentation
DOCS-1258 typo

Signed-off-by: Sam Kleinman <samk@10gen.com>
Fix grammatical problems.

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