Git commits in Moodle 1.8.4 by pichetp

commit 5e0da4b5ee566807d51327d0cabca45f2cfa9ba2
Author: pichetp <pichetp>
Date:   Thu, 01 Nov 2007 09:36:04 +0900
Tag:    v1.8.4

MDL-11867 setting real null when response is null in calculated question merged from  head

commit 439e93b27f8f189032f472dcdd6dc6647e13807c
Author: pichetp <pichetp>
Date:   Wed, 31 Oct 2007 11:44:34 +0900
Tag:    v1.8.4

solving MDL-7496 for calculated merged from head

commit 5234b782325989757aea9a349640161fbb108020
Author: pichetp <pichetp>
Date:   Wed, 31 Oct 2007 11:34:33 +0900
Tag:    v1.8.4

solving MDL-7496 for calculated merge from head