[PATCH]: Allow errors in parameter values to be reported during the BIND phase itself..

For example:

$ python3.5 -c "import pg; db=pg.DB(); q = db.query(\"SET log_parameter_max_length_on_error=-1;\"); db.prepare('p', 'SELECT \$1::smallint'); db.query_prepared('p',66666);"
2021-01-03 02:21:04.547 CST [20157] ERROR:  value "66666" is out of range for type smallint
2021-01-03 02:21:04.547 CST [20157] CONTEXT:  unnamed portal with parameters: $1 = '66666'
2021-01-03 02:21:04.547 CST [20157] STATEMENT:  SELECT $1::smallint

When there are many bind params, this can be useful to determine which is out
of range.  Think 900 int/smallint columns, or less-wide tables being inserted
multiple rows at a time with VALUES(),(),()...

Of course, this isn't as good as showing the column name, so I might pursue
Tom's suggestion for that at some point.

-- 
Justin