Use proper grammar for SMTLIB output.

To handle the case when more complicated output is received from SMTLIB,
properly parse SMTLIB output.

Due to ANTLR trying to consume the full stream, the SMTLIB response is first
put in a string.  A simple algorithm, using the brackets, is used to find the
beginning and end.

git-svn-id: https://groke.mcmaster.ca/svn/grad/colin/branches/TableTool_javization@10722 57e6efec-57d4-0310-aeb1-a6c144bb1a8b