- Make the range-et-al optimizer produce E(#table records after table 
                                           condition is applied),
- Make the join optimizer use this value,
- Add "filtered" column to EXPLAIN EXTENDED to show 
  fraction of records left after table condition is applied
- Adjust test results, add comments

The idea is to add DEFINER-clause in CREATE PROCEDURE and CREATE FUNCTION
statements. Almost all support of definer in stored routines had been already
done before this patch.

NOTE: this patch changes behaviour of dumping stored routines in mysqldump.
Before this patch, mysqldump did not dump DEFINER-clause for stored routines
and this was documented behaviour. In order to get full information about stored
routines, one should have dumped mysql.proc table. This patch changes this
behaviour, so that DEFINER-clause is dumped.

Since DEFINER-clause is not supported in CREATE PROCEDURE | FUNCTION statements
before this patch, the clause is covered by additional version-specific comments.

mysqldump skips information_schema db
'use' now can use information_schema db
changed value of column 'Null' to 'NO' if column is not nullable

I learned that one shouldn't use String::set in val_str() methods...

More tests.
Better error messages.
Fixed bug when checking if we updated all needed columns for INSERT.
Give an error if we encounter a wrong float value during parsing.
Don't print DEFAULT for columns without a default value in SHOW CREATE/SHOW FIELDS.
Fixed UPDATE IGNORE when using STRICT mode.

CREATE TABLE t1 SELECT POINT(1,2); fixed

This bug is the result of weird error happening with mi_float8get and double
arythmetic. I described that in 'Bug that looks potentially dangerous' email

test for IGNORE added

code covarage for srid, GeomFromText with 2 parameters
code covarage foe print() method of gis functions

SHOW COLLATION columns have been removed:
  D -> Default
  C -> Compiled
  Y -> Yes

Character set is not displayed in "Type" column anymore
In "Collation" column NULL instead of BINARY is now displayd for for non-character data types

LINEFROMWKB(), LINESTRINGFROMWKB(), MLINEFROMWKB(), MPOINTFROMWKB(),
MPOLYFROMWKB(), MULTILINESTRINGFROMWKB(), MULTIPOINTFROMWKB(),
MULTIPOLYGONFROMWKB(), POINTFROMWKB(), POLYFROMWKB(), POLYGONFROMWKB()
functions have been added (as synonyms for GEOMFROMWKB()).

geometry type (POINT, LINESTRING, etc)
and changed all into "GEOMETRY".

Point, MultiLine, Poligom, etc, are now not aliases
for Geometry, but separate field types.

GeomertyFromWKB() function.
SRID() function.
::store() methods for Field_geom.
Code cleanup.

Added Centroid(), Area() tests for MultiPolygon objects.