fix size-related bug

compiling on 64-bit, NODE_SIZE is 64. was using 48, leading to
bad initialization bugs.

restored use of bags.
link with iconv
more unit tests
stub implementation of IsTextUnicode
add more basic tests
remove trailing whitespace
remove dlmalloc
Revert "remove dlmalloc"

This reverts commit 19cb78344bc4970c3d4178c15aea9025aa2b7dc8.
remove dlmalloc
port more tests over; test A->W conversion