Supports table_name prefix/suffix for add_foreign_key

Closes reenhanced/oracle-enhanced#1

LGTM given by: @codenamev

Squashed commit of the following:

commit b1c0fedfca69cde2d20ea362ea738afd422e516e
Author: Nicholas Hance <nhance@reenhanced.com>
Date:   Tue Dec 11 11:16:39 2012 -0500

    typo

commit 6f776e4589a2a0e6873d1d624428db29bfae904d
Author: Nicholas Hance <nhance@reenhanced.com>
Date:   Tue Dec 11 11:07:25 2012 -0500

    Supports table_name_suffix for add_foreign key

commit db3c2655a7717905443348f576e4a278942ce903
Author: Nicholas Hance <nhance@reenhanced.com>
Date:   Tue Dec 11 10:44:34 2012 -0500

    Support table prefix for add_foreign_key