implement field escaping with field
apply test from chrisichris patch for escaped symbols
i think line wraps in field names are still not needed... ;)
document copy, identityHash and mapHash functions
document the delete function
support opaque typedef in parser
support creating opaque types
opaque type cast unification part
implement casting to opaque types
don't convert on opaque cast
add hidden types free variables to the opaque typedef
copy hidden type on as cast
support opaque types in modules
opaque type support is done
opaquetype -> opaquelist
opaquetype.yeti -> opaquelist.yeti
disallow free type variables in opaque types as unsound
fix opaque type cast
don't mess with as error message on java casts
declare opaque as part of type in vim syntax