more sophisticated javascript types + rendering.
Javascript arrays.
compilation to the new backend.
use the new backend in main.hs
require mtl and transformers
Cleaned up some rendering code; fixed 'indent', got rid of 'line'.
unified all of the comma-shuffling
'expression' places commas in between lines of an Object.
indent the last brace of a function.
a little bit nicer concatenation in 'main'.
make sure to pass "element" to all calls.
try not to delete everything except the returned value.

oops.
Assignment takes two expressions.

clearer lhs/rhs distinction coming soon.
updated compilation for new Assign. also compile reassignments.
functions should behave as functions returning blocks.