[OGR provider] Field type declaration: update with more sensible valu…

…es for min/max length

In particular put 0 as minimum length for integer, integer64, real and text fields,
so as to let OGR decide the default (and not limit text fields for format that
don't have limitations)

src/providers/ogr/qgsogrprovider.cpp

@@ -400,12 +400,12 @@ QgsOgrProvider::QgsOgrProvider( QString const & uri )
   open( OpenModeInitial );
 
   mNativeTypes
-  << QgsVectorDataProvider::NativeType( tr( "Whole number (integer)" ), "integer", QVariant::Int, 1, 10 )
+  << QgsVectorDataProvider::NativeType( tr( "Whole number (integer)" ), "integer", QVariant::Int, 0, 11 )
 #if defined(GDAL_VERSION_NUM) && GDAL_VERSION_NUM >= 2000000
-  << QgsVectorDataProvider::NativeType( tr( "Whole number (integer 64 bit)" ), "integer64", QVariant::LongLong, 1, 10 )
+  << QgsVectorDataProvider::NativeType( tr( "Whole number (integer 64 bit)" ), "integer64", QVariant::LongLong, 0, 21 )
 #endif
-  << QgsVectorDataProvider::NativeType( tr( "Decimal number (real)" ), "double", QVariant::Double, 1, 20, 0, 15 )
-  << QgsVectorDataProvider::NativeType( tr( "Text (string)" ), "string", QVariant::String, 1, 255 )
+  << QgsVectorDataProvider::NativeType( tr( "Decimal number (real)" ), "double", QVariant::Double, 0, 20, 0, 15 )
+  << QgsVectorDataProvider::NativeType( tr( "Text (string)" ), "string", QVariant::String, 0, 65535 )
   << QgsVectorDataProvider::NativeType( tr( "Date" ), "date", QVariant::Date, 8, 8 );
 
   // Some drivers do not support datetime type