Fix SQL when ANSI_QUOTES is enabled in mysql config.

> http://dev.mysql.com/doc/refman/5.1/en/server-sql-mode.html#sqlmode_ansi_quotes

> When ANSI_QUOTES is enabled Mysql treats double quotes the same as backtick quotes, ie as an identifier.

> This patch changes quotes round anything that is not an identifier and makes the SQL work with ANSI_QUOTES on & off.

Closes #173 ; rebased + updated specs.