to_sql if_exists argument with SQL server and other schema
The `if_exists` argument of the `to_sql` function doesn't check all schema for the table while checking if it exists. Furthermore, it inserts to the default schema, causing somewhat contradictory behavior.

For example, while using SQL Server with my default schema set to `test`, `to_sql` inserts the table into `test.table_name`. However, trying this again, with `if_exists='replace'`, `to_sql` finds no table of the name `dbo.table_name`, and then tries to create `test.table_name`, causing an error.

Details :

http://stackoverflow.com/questions/24126883/pandas-dataframe-to-sql-function-if-exists-parameter-not-working
