Improve the create database UI

1. Remove the attribute "Number of pages"(Refer to the attachment "Figure -1").
2. Change DB volume_size and LOG volume_size default value to 512M (Refer to the attachment "Figure -1").

3.When you change "Page size", Volume size should not be changed(Refer to the attachment "Figure -2').

4.The existed volumes size should be used in the db_volume_size value of cubrid.conf. Also, the "Volume size" should be same as the db_volume_size value of cubrid.conf in "Additional Volume Information"(Refer to the attachment "Figure -3").
5. Currently, "Volume size" also should be the db_volume_size value of cubrid.conf in Automatic volume extension dialog.
And, currently "Using automatic additional volume" checkbox is disabled as default.
But, when some newbie user do not use, it can be extended automatically generic volume.
Therefore, it will be enabled as default.(Refer to the attachment "Figure -3").