spidermonkey: remove caveats

MongoDB now uses v8.
Fix geoserver 2.3.0 sha hash

Fixes bad hash for geoserver 2.3.0

Closes #18593.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>
ffmpeg: enable VDA for HW decoding on OSX

Closes #18583.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>
sqlite 3.7.16

Closes #18592.

Signed-off-by: Misty De Meo <mistydemeo@gmail.com>
superenv: move MacSystem into separate file

This makes it requirable before superenv becomes active.
superenv: move check logic into superenv?