Copy from srfi-9 document.
  http://srfi.schemers.org/srfi-9/srfi-9.html
Support util.record library
First commit of supporting srfi-9.
Display the variable name as Lisp variable name insead of internal symbol name in error message.

fix:     "Error: undefined variable aaa_bbb"
before:  "Error: undefined variable _aaa_MIMARKbbb"
Rename test directory to spec directory for merge.
Merge branch 'support-srfi-9'