Refactors AST nodes to reflect teiid engine packages

* Moves org.teiid.query.sql.lang.symbol classes to
  org.teiid.query.sql.symbol

* Moves org.teiid.query.sql.lang.proc classes to org.teiid.query.sql.proc

* Adds the boilerplate for Array being generated through both javacc and
  the TeiidNodeFactory
WIP