misc fixes
update escodegen to handle ComputedPropertyKey
CoffeeScript -> ES6: it has begun
improvements for object/class computed property name support
an es6 stack class
get this compiling
terrible, but we need to make the map keys unique.  time to upgrade node to something with a working Map
defaults can contain nulls
move intrinsic to echo-util, and a bunch of minor fixes
es6 implementation files
make analogous fixes to the js passes from closure-conversion.coffee, and get everything compiling individually
fix loads of compiler errors
does anything even use ClassHeritage?
typos caught by ES6 work
more ES6 conversion work
add getInt1Ty
somehow we get a \n in LLVM_LINK_FLAGS.  not sure how that happens.
yay, we get a usage message from ejs-es6.js.exe
tag functions for tagged templates take substitutions as a rest parameter, not an array.
use relative paths starting with '.' so traceur doesn't try to look for things relative to the root js file