fix #82 ( `:D` Operator with String key)

[BlazingTwist]

Dev test:

aya> "value" "key" {,} :D
{,
  "value":key;
} 

aya> "value" ::sym_key {,} :D
{,
  "value":sym_key;
} 

aya> "value" ["list" ::of "keys"] {,} :D
{,
  "value":of;
  "value":keys;
  "value":list;
} 

Resolves #82

[BlazingTwist]

I felt that the operand order for errors was misleading. (It says that it expects the Dict as the last operand, but outputs it as the first)

aya> "value" "key" "dict" :D
Type error at (:D):
    Expected ((ASD|AJD))
    Received ("dict" "key" "value" )
   in :D .. }

The second commit changes the order, so that it matches the DocTypeStr

aya> "value" "key" "dict" :D
Type error at (:D):
    Expected ((ASD|AJD))
    Received ("value" "key" "dict" )
   in :D .. }

[nick-paul]

Looks great! Thanks!