added docs to clarify that sql statement is already in a dialect
Merged zzzeek/sqlalchemy into master
- fix minor spelling error
Merged in jvanasco/sqlalchemy-alt/issue_docs_event_statement (pull request #33)

added docs to clarify that sql statement is already in a dialect
Merged in jon_nelson/sqlalchemy/minor_spelling_error (pull request #37)

- fix minor spelling error