Convert remaining Animatable lines to Animation type lines.

[dbaron]

[css-backgrounds-4][css-box-3][css-color-hdr][css-module][css-writing-modes-3][css-writing-modes-4] Convert remaining "Animatable" lines to "Animation type" lines.

See #72.

[svgeesus]

This all looks good, but what does Animatable: n/a mean? Is it the same as not animatable?

[yarusome]

This resolution implies that writing-mode should be "not animatable", but the final resolution says differently from the proposed one.

[dbaron]

This all looks good, but what does Animatable: n/a mean? Is it the same as not animatable?

The "n/a" values are for a propdef table that's for an alias rather than a real property. (Perhaps aliases should be more like shorthands and say "see aliased property" or something like that.)

This resolution implies that writing-mode should be "not animatable", but the final resolution says differently from the proposed one.

Based on that resolution I agree that like writing-mode, direction, and unicode-bidi should all be not animatable rather than discrete. But I don't see anything in this PR that's changing those properties.

[svgeesus]

LGTM