Fix strangely broken toString/fromString for Integer.
Fix broken stable pointer equality.
We already have JS-native round; remove comment about it.
Remove unused module Haste.Optimize.
Optimize [a,b,c][1] into b and similar.
Eliminate comparisons with true/false in ?: expressions.
Let data constructor tags start at 0 rather than fIRST_TAG.

This enables some minor space optimization, as we can now match the first
constructor of every type with !foo[0] rather than foo[0]==1.
Unpack all enumeration types, not just booleans.
NOINLINE vals in StableNames test.

Probably does nothing ATM, but you never know what GHC may do in the future.
Add test case for tagToEnum#/dataToTag#.
Fix TagToEnum test so it doesn't crash GHC.

Worked fine in Haste, but caused a CASEFAIL in GHC. Strange.
Add tagToEnum# primop. Fixes #68.
Update doc/js-externals.txt with the new constructor tags.