so sick of the namespacing of symbols, just use some c++ namespaces.
we don't need llvm.ConstantAggregateZero, as llvm.Constant.getAggregateZero already exists.  also we don't need echo-desugar or typeinfer
a few misc fixes for self-hosting.  add dense array element reallocation (really?  I couldn't be bothered to write this before?), fix string.fromcharCode now that we have ucs2 characters, add the Error type, and implement parseInt.
add a parseInt test