Unable to compile file containing dictionary literal

[h3rald]

The following valid min program cannot be compiled:

{
    1 :a
    2 :b
} puts!

Produces:

$ ./min compile test_compile.min 
    Generating test_compile.nim...
(!) (1,1) []: test_compile.min [l:4, c:1] ERROR - Undefined or invalid value (tkBraceRi): }